FAQ

GWS Top electric flight FAQ, please check one of the below questions to find out it’s answer.
☆ Note: If your question not listed in Top Questions below, please email our customer service at service@gwsus.com or call our number at 1-909-332-2929.

AUX CIRCUIT

1. PHA-01 Mixerboard Panel Instruction
(1) 3 in one mixerboard adjustment
*Main: 2- pin header for main motor.
*Tail: 2-pin header for tail motor.
*Mixer Gain: “+” (clockwise) increase the tail motor output,“-“ (counterclockwise) decrease the tail motor output.
*Gyro Gain: “+” (clockwise) increase the ability of gyro to balance the helicopter (stable but less active),“-“ (counterclockwise) decrease
the ability of gyro to balance the helicopter (active but less stable).
*SW: #1 reversing switch for gyro. #2 Spare. (Both switches are set to the correct positions at GWS HQ)
(2) Adjustment Instruction:
(Please disconnect the battery before any adjustment. Please reset the mixerboard by re-connecting the power after any adjustment.)
*With Motor 150: The Mixer Gain is set to around 2 ~3 o’clock direction & the Gyro Gain is set to Maximum.
*With Motor 300: The Mixer Gain is set to around 12 ~1 o’clock direction & the Gyro Gain is set to Maximum.
The above setting is for beginner to control and maneuver the GWS Dragonfly easily.
*For advanced flyers, you can adjust the mixerboard based on your skills and preference.
Due to the aging of motors, the performances of motors decrease. You can balance the helicopter by adjusting mixer gain.
Please refer to the PHA-01 Instruction Manual for details. If the motor(s) performance deteriorates (RPM or power decreases and you cannot maneuver the helicopter properly by any adjustment the mixerboard, please change the motor(s).

In responding to your question, please be informed that you can't use the trainer cord jack or USB port adapter for running the FMS simulator program. We have special design for this. Please check below:
1. For JR system--Use GW/FSM
2. For Futaba system -- Use GW/FSM with an adapter (GW/FSM-A)
3. For GWS Tx -- Use GW/FSM-T4AII

BEGINNER TOPICS

Generally speaking, you need equipment that is very similar to what other RC flyer’s require. There are only a few primary components: the radio, the battery, the charger, the aircraft, the speed control, and the motor. The amount of accessories you purchase are up to you, but most people typically buy things like a soldering iron, flight box, volt/amp meter, etc. The electric RC specific components as below:
Battery:
The battery pack is what provides power to the motor. Typical packs are composed of 500 to 2000 mAh cells. ("milli-amp hour")
The weight of the pack is proportional to its capacity.
Charger:
The charger is used to charge the battery packs. There are three primary charging ways providing you: trickle, fast, and peak.
1. Trickle charging is a low-current charge that takes several hours to perform but is guaranteed to not hurt the battery.
2. Fast charging involves stuffing energy into the pack at a high rate so it is charged in as little as 15 minutes, with some danger that the pack will be damaged if it is not monitored. Most low-end chargers provide both fast and trickle charging. GWS chargers use a type of fast charging called peak charging.
3. GWS chargers simply monitor the charge automatically so the pack cannot be hurt by fast charging. If you are going to be at all serious about electric flight, buy a GWS charger.
Aircraft:
As the most part, the aircraft is the same as ones powered by internal combustion. But the electric systems are heavier than their equivalent IC counterparts, so electric aircraft are usually built much lighter than IC aircraft. Most IC planes are overbuilt anyway and can be easily lightened.
Speed Controller:
The GWS speed controller provides aircrafts proportional throttle control by varying the amount of power that is transferred from the battery to the motor.
Motor:
GWS has a vast supply of different motors to experiment with ferrite motors are much more expensive. These are very expensive, but provide an even wider range of output possibilities at high efficiency. The motors in GWS that are supplied in beginner’s kits are a type of ferrite motor. The motors provided by GWS will enable to fly excellent with your first plane.

Well, we’ll happy to give you an idea of what it takes to get started.
1.High wing electric trainer of GWS products.
Try the BN-2, E-STARTER, BEAVER, SLOW-STICK, etc.
2. Building materials
3. Battery packs (2 7-cell 1400 mAh packs)
4. Speed controller
5. GWS peak charger
6. 4 channel radio above
This list will bring you a nice flying airplane with plenty of room to grow. You could do with somewhat less expensive components; in this way, you will be able to use the same radio, charger, speed control, and batteries on your next plane. You don’t need two battery packs, but having two packs is better just because one can charge while you are flying with the other.

This is the way to go if you can afford the equipment.

You may go to a local hobby store and find out the clubs in your area. Clubs provide training, flying fields, auctions, competitions, fun-fly events, newsletters, and, best of all, lots of advice for beginners. R/C clubs are the best resource you can have. Most clubs require you to become an AMA (Academy of Model Aeronautics) membership which costs $48(1999) and provides you with a free magazine subscription and insurance coverage.

Any plane can fly with electric power will be good. This includes helicopters and ducted fan jets. There are also an increasing number of planes that are only practical with electric power, for example GWS indoor models and park fliers.

However, there are tradeoffs that must be considered with your electric power systems. For example, in order to increase duration, you must be willing to accept increased weight (wing loading) and/or decreased power. The three characteristics are interdependent. For a particular cell technology (NiCad, NiMH etc), the weight per cell is proportional to capacity, the relationships can be shown as GWS R/C plane’s instructions.

We’ll have a breakthrough in battery technology that allows us to store 4 or 5 times more energy in a cell, these tradeoffs will be the central issue of electric aircraft design.

There are many normal modeling tools like knives, wrenches, abrasive paper etc that are as useful to you as to any other modelers. You can get started in electrics with very few specialized tools. But there a few that will make life so much easier that you will soon wonder how you did without them.
The few tools you really should have are :

1. Soldering Iron
(NOT a soldering gun). Essential for general wiring. If you only have one it should be around 25W. If you are going to make your own battery packs a larger iron will help, preferably at least 40W (I use a 100W Weller iron, carefully).
2. Multi-meter
It is not worth buying an analog meter. You can get a simple digital multi-meter for very little from stores like Radio Shack. If you can get one that will read DC current up to at least 20A that will be helpful (or see Whattmeter below). But even the simplest will let you measure voltages accurately so you know what is going on in your power system and will also provide a way of checking continuity so you can make sure all your wiring is intact.

Other potentially useful tools include:
3. Whattmeter
A device which simultaneously measures and displays voltage and current and will also show the total energy used. It is very much like the displays on most good chargers but with the great advantage that you can put it anywhere in the circuit and so measure EXACTLY what is happening. It is unbeatable for finding out (rather than guessing) what current you are using and how the battery voltage goes down as the current increases. It will also allow you to measure your own motor constants which is very useful if you want to experiment with odd (perhaps cheap surplus) motors.
4. Crimp Tool
Depending on what type of connectors you decide to standardise on you may find it worth getting a crimping tool. The one I use for Powerpoles is quite expensive but makes it so much easier to fit the connectors and makes a much better joint than a soldered joint.
5. Tachometer
A good tachometer is very useful if you want to do some investigating of electric power sources. Even the most basic of motor parameters involves knowing the speed at which the motor is rotating.
6. Digital Scales
All planes fly better if the airframes are light and this is especially true of electrics where the power package makes up such a high proportion of the overall weight. It is probably most important to get scales that can weigh small amounts fairly accurately (down to 1/10 oz) since you will be saving weight wherever you can. Some of the best value to be found is the used postal scales that are sometimes available.

These will be fine unless your ambitions lie in the direction of very small and light indoor models. Since the lightest of these have a total flying weight of well under 1 oz you will need jewellers scales.

ELECTRIC MOTORS

Gearing allows a motor to turn a larger prop at a lower rpm. This allows the system to produce more thrust while drawing the same number of amps. The trade-off is that top speed is reduced, which makes gearing suitable mostly for slow-flying aircraft. Sport electric planes are usually run with a direct drive system.

If you are looking for a watts to horsepower conversion, then the formula is: 1 brake horsepower = 750 watts. The problem is that electric motors have many more variables than ic engines. In order to determine the performance of an electric motor, you must first answer questions such as how much duration you want, how much power you need, etc. Gearing also heavily influences the comparison.

At room temperature, according to the industry standard is 1 watt per square inch for continuous operation (24 hours).

It’s about 3 watts for ours for as long as a NiCad pack can run it.

If commutator has deposits of carbon and gunk on it you can clean it with scotch rite or a com stick. Very light polishing action. You can also clean off gunk when motor is running by a few drops of alcohol.

If com is pitted or shows brush skipping and chattering your com has been overheated and needs to be returned. It is out of round. polishing will not cure out of round.

You need a lathe with a ball bearing in the tail stock and a diamond tool..or at least a sharp cutting tool.

Of the 3 motor constants Kv and Io are much easier to measure.

Kv: With the motor shaft in a drill press running at a known speed measure the voltage at the motor terminals. Kv = speed / voltage i.e. if the speed is 6000 rpm and the voltage is 3V
Kv = 6000/3 = 2000 rpm/V

Io: Simply run the motor with no load (no propeller)and measure the current taken. That's Io. You can use almost any voltage because the current does not vary with voltage. However the motor will still be turning at the rpms defined by V x Kv so don't go too mad. I usually use 5V.

Both Kv and Io should be measured with the motor neutral timed. For most can-type motors this is what they are fixed at. If you do have a motor with adjustable timing then you can try (carefully) adjusting it as you measure Io. It will be neutral timed when Io is at its lowest value.

Rm: this takes a little more work. The motor and shaft must be held so that neither can move i.e. the motor is stalled. You then need to apply a voltage through a limiting resistor and measure the current through the motor and the voltage at the motor terminals. Note it must be directly at the motor terminals NOT the power supply. You will need to do this very quickly as the current will be high and the motor will quickly get very hot. Rm is voltage / current.

E.g. if you measure 5A and 1.2V then
Rm = 1.2 /5 = 0.24 ohm, a typical value for a Speed 400.

It is a good idea to fit at least 2 capacitors to most brushed motors to cut down on the radio interference which the motor may generate. The same capacitors can be used for all brushed motors, the value does not change with the size or power of the motor. The capacitors should be soldered from each motor terminal to the motor case. For extra security against interference you can also fit a third capacitor between the 2 motor terminals.

CHARGERS

When a Ni-Cad battery is charged and its voltage increases. It is a basic characteristic of these batteries that when they are fully charged the voltage levels off and then goes down very slightly. The chargers look for this small change in voltage and terminate the charge when they notice it. Note that some chargers drop into a maintenance trickle mode but beware of this. In some cases the trickle charge is much too high for the battery to be left for a long time and so the battery can be overcharged even on the "trickle" rate.

First of all, make sure of the rate for a given length of Charging and use the following rule: amps = Capacity / time to charge e.g. to charge a 1200 mAh battery in 20 minutes requires a current setting of 3.6 amps: amps = 1200 mAh / .33 h = 1.2 ah * 3 h =3.6 amps. The same rule can also be reworked to determine how long it will take to charge a battery at a given current: time to charge = Capacity / amps e.g. The time it takes to charge a 1500 mAh battery at 5 amps is 18 minutes: time to charge = 1500 mah / 5 amps = 1.5 ah / 5 a = .3 h = 18 minutes. The charging process is not totally efficient some of the energy is lost as heat and the charging takes place a little longer than this.

MC 2002 can charge 4~12 cells of 50~3000mAh Ni-MH or Ni-CD battery packs rapidly at three charge rates of 1C, 2C and 1/2C. Please check http://www.gws.com.tw/english/service/book/aux_manual.htm for more details.

Take a battery capacity of 1000mAh as an example:
1C: uses 1000mAh (1A) charge current to battery (the charge current is equal to the battery capacity).

It takes about an hour to be fully charged.
2C: uses 2000mAh (2A) charge current to battery (the charge current is 2 times of battery capacity).

It takes about half an hour to be fully charged.
1/2C: uses 500mAh (0.5A) charge current to battery (the charge current is half of battery capacity).

It takes about two hours to be fully charged.
According to these examples above, we can know that it takes about 20 minutes for 3C (3A) and 15 minutes for 4C (4A).

NO ! Please don't try it. Our standard charger will very quickly destroy Lithium batteries of all types. They need very special charging methods which are different for each Lithium cell type. Even you try to charge with a slow charger can do damage.

Absolutely GWS standard slow or trickle charger as supplied with most radio systems will work with both NiCad and NiMH batteries. For fast charging, it's best to use a charger which specifies that it is suitable for NiMH. Since the characteristics of NiCad and NiMH cells are slightly different, the best chargers have different programs which allow them to terminate the charge in various ways.

Generally speaking, the Australian power plug for charger is 240V 2 pin, as / shaper.

DESIGN SUBJECTS

We’ll have some explanations why series connections are better than parallel but the biggest reason is efficiency. If you hook the motors in series the noload current of both motors is equal to the no-load current of the individual motors so you don't have to suffer in that area.

FLIGHT GLOSSARY

  • BEC:
  • Battery Eliminator Circuitry. This feature enables a speed controller to operate a receiver from the same battery that the motor uses. BEC saves weight, as it eliminates the receiver battery.

  • C:
  • A charging rate of C is that which will in theory fully charge a cell in 1 hour. It's actually the same number as the cell capacity but expressed in mA not mAh. E.g. for a 2000 mAh cell the C rate is 2000 mA i.e. 2A.

  • Can Motor:
  • Another name for a FERRITE MOTOR

  • Capacity:
  • Usually battery or cell capacity. It is measured in Amp Hours (AH) or more commonly milliAmp Hours (mAh). 1 AH = 1000 mAh = the ability to deliver a CURRENT of 1 Amp for 1 Hour, or 10 Amps for 6 minutes (1/10th of an hour), or 30 Amps for 2 minutes etc. Note that this is not related to voltage. It a characteristic of the CELL type. To get greater VOLTAGE you add more CELLS.

  • Charger:
  • Device used to recharge PACKs, usually from a 12V car/leisure type battery. These come in a wide range of prices and specifications. The main things to look for are the number of cells they will charge and the maximum current they will deliver. You will find a price jump from chargers which charge up to 7 cells and those over. That's because to charge more than 7 cells from a 12V battery requires special circuitry to increase the available voltage.

  • Cobalt Motor:
  • This term is generally used for brushed (conventional) motors with rare earth magnets. Some of these (Astro) actually use cobalt as the brush material but there are other materials used. Regardless of the precise material these are all commonly, if inaccurately, called cobalt motors.

  • Energy Density:
  • Characteristic of a cell. It is basically a measurement of how much CAPACITY you get for each unit weight. Since the cells are usually a high percentage of our total weight the higher this is the better. If you could get a 2000 mAh cell that weighs only half the conventional ones you would save a lot of weigh from the plane.

  • ESC:
  • Electronic Speed Control. This device is the equivalent of a throttle for electric motors. It controls the power into the motor. Many ESCs are also fitted with other facilities like BEC (see above), a brake (to stop the motor windmilling and allow folding propellers to close properly)

  • Ferrite Motor:
  • Brushed (conventional) type of motor with low cost ferric oxide magnets.

  • Folder:
  • Folding propeller. When the motor is not running the prop blades fold alongside the fuselage for lower drag (and you don't break so many blades on landing). Typically used with powered gliders.

  • Hi-rate:
  • A hi-rate speed control switches at a high frequency, usually at around 2 to 3000 times per second.

  • IC:
  • IC stands for "internal combustion." I use this term to refer to all the various kinds of fuel-driven engines: gas, diesel, glow, etc... (i.e. the "normal" R/C power plant).

  • Internal Impedance:
  • This is the main characteristic of a CELL which limits the maximum current you can get out of it. So far NiCds have by far the lowest internal impedance available.

  • lo-rate:
  • A lo-rate speed control switches at the same frequency as the servo signal. Roughly 50 times per second.

  • Opto-coupling:
  • Indicates that the electrical current for the power system is isolated, which makes motor-induced radio interference less likely. The design of opto-coupling makes it impossible to incorporate with BEC.

  • Soft start:
  • Some electronic switches will ramp the current up over a small time (often less than a second) when you switch on. This greatly helps to reduce wear and tear on motors and particularly gearboxes. Some ESCs also claim this feature though it only really does anything if you slam the throttle wide open from zero.

BATTERY PACKS

A GWS battery pack consists of a number of cells, wired in series. Therefore, the voltage for the pack is equal to the number of cells times 1.2 volts (NiCad cells provide 1.2 volts of electricity). However, because of a cell's internal resistance, the actual voltage you are getting is slightly lower; more like 1.1 volts per cell or even down to 1 volt per cell in the higher current installations.

Different cells can withstand different charging rates. Checks with the instructions to make certain you don’t damage your pack. For fast charging, most packs can be safely charged in 15 minutes, which requires a charging current of 4 times the capacity of the pack. Slow charging is usually done at a rate of 1/10th the capacity, or C/10. GWS lists this as the charge rate in which the cells will not vent (release gases that build up from overcharging). However, even this charge rate can reduce the life expectancy of a cell if left on after the cell is fully charged.

A GWS peak charger automatically does this. If you don't have a GWS peak charger, we'll provide the way to monitor the charge yourself. You'll simply stop charging when one of the following two things occur: 1. The pack starts to get warm. 2. The charging voltage starts to drop. SECURITY WARNING: if you are doing a manual fast charge (I.e. by watching the temperature and/or voltage yourself: PAY ATTENTION! If the batteries get too much charge they will overheat and that could damage or even destroy your batteries!

Suggest to adjust the knob of the charger to make charging current at 6A (the maximum) and charge for 30 mins.

A GWS peak charger automatically does this. If you don't have a GWS peak charger, we’ll provide the way to monitor the charge yourself. You’ll simply stop charging when one of the following two things occur: 1. The pack starts to get warm. 2. The charging voltage starts to drop. SECURITY WARNING: Doing a manual fast charge (i.e. by watching the temperature and/or voltage yourself: PAY ATTENTION!), if the batteries get too much charge, they will overheat and that could damage or even destroy your batteries!

We didn't have the figure for that. However, our R/D suggests to unplug the battery when you can feel the battery's outside case started to warm. When charging the battery with the slow charger, be sure to watch over the time, or the battery will be damaged probably.

The milli-amp hour is the standard unit of storage capacity for a cell.

It is similar to "gallons of fuel" for an internal combustion engine. The milli-amp hour rating of a cell tells how many constant milli-amps of current can be supplied by the pack for one hour. This rating can be used to find the duration that a battery pack can provide given a certain draw.

Because cells are wired in series, the milli-amp hour rating of a pack is the same as the milli-amp hour rating of a single cell.

NiMH (Nickel Metal Hydride) cells are similar to the more familiar NiCad’s in many ways. A cell has a voltage of 1.2V and they are made in the same range of sizes. As compared with NiCad, NiMH cells of the same size and weight generally have a higher capacity (mAh) but cannot be charged or discharged quite so fast. They have a higher internal resistance so they will not deliver as much current as NiCad’s. They can be very useful for sport flying where good duration is preferred to the ultimate in power and they are particularly useful for indoor and slow flight when their relatively light weight for capacity is prized.

Like all battery technologies NiMH cells are improving all the time. At the time of writing the best of the bunch are the new 3000mAH cells in Sub-C size, capable of currents over 30A.

It means 8 cells 9.6V 750mAh batteries.

The "mAh" is the standard unit of storage capacity for a cell. It is similar to "gallons of fuel" for an internal combustion engine. The "mAh" rating of a cell tells how many constant milli-amps of current can be supplied by the pack for one hour. This rating can be used to find the duration that a battery pack can provide given a certain draw. Because cells are wired in series, the "mAh" rating of a pack is the same as the "mAh" rating of a single cell.

For 1050mAh : Max. charging rate : 1C ; Max. discharging rate : 6C
For 1300mAh : Max. charging rate : 1C ; Max. discharging rate : 8C

Please be noted that most batteries that are new have to be cycled several times in order to gain their higher voltage and best efficiency.

The maximum current draw for GWS 9.6V 1000mAh Ni-Cd batteries is 10C (10 amp).

Weigh the dangers of cell reversal versus the dangers of NiCad memory and you may decide for yourself.

Some people discharge their packs to 0 volts per cell and say they have never had a problem. Others say that cycling below 1.0 volt is damaging. Use your best judgment.

The average fly duration of 8.4V 750 mAh battery is 5~7 mins.

It can be discharged to 0 volts per cell safely. Cell reversal can't occur with individual cells. As a matter of fact, cycling an individual cell is a good way to determine its exact capacity.

No, we’ll give you a warning first. Base on many factors, we do recommend that not using this method for your electric flight.

According to GWS security instructions of Ni-Cad and Ni-MH cells, there is a very definite instruction that you should never solder directly to the cells. The reason for this is that the cell has a number of components which are made of plastics and which can be damaged by excessive heat. In particular there is a vent designed to allow excess hydrogen to be safely removed from the cell. If you damage the vent, oxygen from the air can enter the cell and the internal chemistry will be severely degraded, dramatically reducing the life of the cell.

3 cell 1500 lipo is not yet finished at this moment. GWS will procced on 1300 lipo & 2200 lipi production soon.

For charging 3000 Ni-mh batteries,e suggest to adjust the knob to make charging current at 6A (the maxima) to charge 30 mins.

Since you are using a PRO-TECH model we are not able to provide you with the exact information.If you use GWS charger,all charging information on the instruction manual you can get.However,our engineer advised,it is 2 time capacityo charge battery pack,according to your statement.

You can use LiPo's with an ordinary speed controller, just so long as you don't go below 3v per cell, off load, both with Himax brushless motors., using CC Phoenix 25 speed controllers which are set up for LiPo to cut off a 7.4v with 3 cell packs have flown for over 10 minutes and then topped up the battery and only got 425mAh back into a 1500mAh pack. LiPo's really are the future and you'll save a fair bit of weight. We have been using them with ESC's not LiPo compatible and its easy enough to land and check battery voltage, having said that you'd notice the degredation in performance well before the packs are over discharged.

RECEIVER

There's no difference on "positive or negative shift" for a receiver. People in France usuall use 41 MHZ. There will be no influence either positive or negative shift. Unless you use 72 MHZ or 29 MHZ, the Futaba/Hitec will be negative shift, the JR/ Sanwa(Airtronics) will be positive shift. As long as you use the receiver in PPM mode, that could be compatible with Sanwa transmitter.

If your frequency of receiver is 72Mhz, please check the switch for JR or FP and PPM(FM) mode.

Please visit our web site http://www.gws.com.tw/english/service/book/airplane_manual.htm for more information of Receiver connections. If any questions pls welcome to contact with GWS through Web-site.

There's no difference on "positive or negative shift" for a receiver. People in France usuall use 41 MHZ. There will be no influence either positive or negative shift. Unless you use 72 MHZ or 29 MHZ, the Futaba/Hitec will be negative shift, the JR/ Sanwa

Firstly please confirm your frequency of receiver in correct range (e.g. 72Mhz or other available range in locate area), afterward to check the switch for JR or FP and PPM(FM) mode.

Yes, our receiver and servos are compatible to Futaba/Hitec.

All GWS products under well quality control. The "J" is made for fit with JR radio. Since your Hitec is rather similar to FUTABA type. You should ask the shop to provide you a R4P "F" type. You'd better bring you TX & other airborne equipment to the shop, make sure every thing is fine.

For R6N receiver with mini crystal, you can choose either Futaba or JR transmitter. Both transmitters are working well with R6N.
If you want to change the TX crystal, you need to buy the GWS standard size crystal (GWX/T36). But it only compatible with JR, not for Futaba.

As you asked about whether our R4P work with JR TX, you have to make sure that the R4P you got is for JR (Shows a J mark on the outside case) and your JR TX has a reception system of FM (PPM). As long as you make sure these, our R4P can work fine with your JR TX.

Our engineer provides our modulation bandwidth spec. fo center frequency as follows :
fo ± 4 KHZ ~ ± 8 KHZ -25dB
fo ± 8 KHZ ~ ± 10 KHZ -45dB
fo ± 10 KHZ ~ ± 20 KHZ -55dB
fo ± Above 20 KHZ -56 + 10 log dB
For your reference.

Please be noted that there are two different sizes crystals made for GWS receivers. One is RX crystal (for Pico/Naro receivers) and the other one is RD crystal (for RD8 & R8M receivers). Please check http://www.gws.com.tw/english/product/receiver/crystal.htm for specific information. As you mentioned you use GWX/RD35 crystal, this is for RD8 receiver not for R4PII. For your R4PII, you have to use GWX1/R crystal to get it work.

SERVO

Please be advised the S136GM is retract servo and S136L MG is just regular servo.

With reference to your inquiry concerning Mini servos. Please refer to our web site at http://www.gws.com.tw/english/product/servo/mini.htm
JR-- (Orange-->Singal) (Red--->Positive +) (Brown-->Negative -)
Futaba-- (White-->singal) (Red-->Positive+) (Black-->Negative-)

#1 set-up - you are correct, it is simply out of spec and will not work at all, or for long. The BEC chip will be almost constantly overheating and shutting down, until the point of failure (closed circuit) with no output.
#2 is fully within specs, and does not pose an issue for even the BEC to shut down from overheating at all, UNLESS a servo is stalled, or the pot is damaged/partially burned/has dead spots and so on. Even good small servos when stalled can draw surprising amounts of current, and with pot damage can basically be a direct short.
The only real (or induced) damage any controllers BEC can cause (we all basically use similar linear regulator circuits) would be from providing less than 5v in an overheating and shutting down situation. Mike from Hitec would know if a constant shutdown-reboot cycle would do anything negative to a servo. From what I know about them, I don't see how it could be harmful#1 set-up - you are correct, it is simply out of spec and will not work at all, or for long. The BEC chip will be almost constantly overheating and shutting down, until the point of failure (closed circuit) with no output.

If you have JR or Airtronics transmitter then you need to purchase the flight pack with JR receiver. If you have Futaba or Hi-tec transmitter then you need to purchase the flight pack with Futaba receiver. Because of high and low deviation please shift / positive or negative.

Please be advised the absolute maximum value of "PICO F STD" is 8 micro second. We would suggest you to use 5 cell (6.0V) battery pack.

POWER SYSTEM

Please be advised that we do not have any idea for the life-span of motor you asked.? Our engineer said that the life of motor is depended on flights at latest 10-20 times or so if it bearful to use. Kindly refer to the following specification of battery.

The maximum take-off weight of EPS-300C is 475g. For a high-wing slow flyer/trainer, we suggest a flying weight of 375g and for a low-wing speedy airplane, we recommend a 320g flying weight.

Our Aero-modeling engineer suggest that you can use GW/EPS-100C-2S power system for better performance, please refer to our web site www.gws.com.tw/english/product/powersystem/eps100c.htm

If you insist to use EP-7060 propeller and 8.4V Ni-MH 350mAh battery on your aircraft, it is ok but the power is less than the EP8060 propeller sets, our engineer says.

We will suggest you that to use EP1080 for EPS power system. We will recommend you to use EP7035 for EDP power system. The best combination would be EP1170 for Direct & EP1180 for slow Flyer if you're using EPS-400C-GS.

Yes, there will be a loss on efficiency when reversing the connectors. It seems that you are planning to use the gear-down power system on a pusher airplane. In this case,? when you reverse the motor and prop, you should gain more efficiency on the motor. Because the motor is already "reversed" on the gear-down power system.? Oppositely, if you plan to use the direct-drive power system on a pusher, the motor will lose efficiency when you reverse the connectors.

SPEED CONTROLLERS

An ESC (Electronic Speed Control) is a device that controls the speed of the motor by turning the motor on and off. Consider the circuit as a diagram shown.

To turn on the motor you disconnect from its plug with Electronic Speed Controller. If you connect and you stop the flow of current and the motor will slow down and eventually stop turning. Proportional throttle control is achieved by varying the amount of time the speed controller is on relative to the amount of time it is off. For example, for 1/2 throttle, the switch in the speed controller is on half the time.

In order to achieve smooth throttle response, this switching in the speed controller must occur several times per second. Inexpensive speed controllers typically perform this switching 50 times per second. The reason why 50 times a second was chosen is because this is the rate that control pulses are sent to each servo and the electronics are greatly simplified if this rate is used. This is called frame rate because the ESC operates at the same rate as the radio control frames are updated.

Please follow below steps:
1. Cut and tear open the shrink tubing.
2. Stick the heat conduction silica film to the flat side of the heat sink, then attach the heat sink to the speed controller.
3. Wear the shrink tubing and use hair drier for fixation.
4. Use a designing knife to cut stripes on the fins of the heat sink, then use the hair drier again.
You may refer to our movie on the below web site http://www.gws.com.tw/english/service/movie/movies.htm.

When a DC motor is spinning with the speed controller turned off it is serving as a generator. With the propeller wind milling the motor (generator now) is producing a voltage at the motor terminals but is doing no work. When you put a short across the motor terminals the motor must now work hard to try to generate the same voltage across a dead short. It might cause the motor (generator) to slow down. The motor short is provided by an electronic switch in the speed control.

This simple responding answer is the efficiency is greatly increased over that of a frame rate control.

An electric motor wants to turn at a certain speed that depends on the voltage that is being supplied to it. Our best speed controller should provide a nice clean DC voltage that varies from a maximum that is the same as the battery down to zero volts.

All GWS electronic speed controllers operate very much like this method.

BEC stands for Battery Eliminator Circuit. The battery eliminating is your receiver pack. The BEC is a completely separate circuit from the rest of the speed control. It is generally a one to two amp linear regulator that converts the motor battery voltage to a regulated 5 or 6 volts to power the receiver and servos

To be frankly with you, a cutoff is a circuit that is added to an esc equipped with a BEC to try to prohibit the motor battery from being run dead and causing a crash when the input voltage goes below 5.25 volts. GWS speed controllers not only have a BEC but have a cutoff circuit. We‘ll highly suggest that you shouldn't use a car type controller in a plane with the BEC active.

There will be schemes shown in GWS airplane’s instructions. Please read the instructions carefully and thoroughly before assembly in order to achieve safe operation with the BEC speed controller.

This might be done if you use a sensor controller and the motors are closely matched. It‘s possible to get some problems with the motor initial startup for this configuration. In order to send the correct signals to the motor(s), the controller has to analyze the configuration. Sometimes one motor may fail to start or may even start in reverse. There is little that can be done about this other than to cut the throttle and try again.

After a number of in-flight failures of the same type of servo under different conditions, I started a thread in another vendor forum asking for help:
Servo failures—what's going on?
In that thread, a number of people have wondered if and how ESCs used under certain (recommended and non-recommended) conditions may have contributed to servo failures without themselves being damaged (i.e. a servo fails, but the ESC is undamaged). That thread seems to have reached a point where more insight on the functioning of ESCs and BECs would be very helpful.

Here are the two set-ups:

1. Pixie 7P, 3 micro servos, 3s lipo, dual IPS ~2 A average draw
2. Phoenix 10, 3 micro servos, 3s lipo, CD rom motor ~ 2 A average draw

In the first case, it has been rightly pointed out to me that the BEC on the Pixie 7P is overloaded with 3 servos on 3s lipo. What would the expected failure be in this case?
In the second case, it is my understanding that the ESC and BEC were not overloaded. Or am I missing something?
It is well worth pointing out that my one and only goal here is to avoid future crashes from servo failure!

I think that servos can be damaged if BEC fails and feeds not 5V as it is designed to do, but full battery voltage-11.1V with 3S LIPO for example.
If it is overloaded(as in too much amp draw from servos with too high voltage) -BEC will shutdown, or loose voltage output to servos, then you loose control of your aircraft. But I don't think that voltage going low can damage servos.
So if you are continuing to use your ESC's and no more servos died it would mean that BEC output is in normal range, you could measure it with voltmeter to be sure.
CC representatives will give you better explanation I hope, as I am not sure how exactly BEC shuts down

Not to stray from Andrew's initial question, I'd like to know the different ways a BEC can fail and the consequences of those different BEC failures. Whether natural or user induced. David

#1 set-up - you are correct, it is simply out of spec and will not work at all, or for long. The BEC chip will be almost constantly overheating and shutting down, until the point of failure (closed circuit) with no output.

#2 is fully within specs, and does not pose an issue for even the BEC to shut down from overheating at all, UNLESS a servo is stalled, or the pot is damaged/partially burned/has dead spots and so on. Even good small servos when stalled can draw surprising amounts of current, and with pot damage can basically be a direct short.

The only real (or induced) damage any controllers BEC can cause (we all basically use similar linear regulator circuits) would be from providing less than 5v in an overheating and shutting down situation. Mike from Hitec would know if a constant shutdown-reboot cycle would do anything negative to a servo. From what I know about them, I don't see how it could be harmful#1 set-up - you are correct, it is simply out of spec and will not work at all, or for long. The BEC chip will be almost constantly overheating and shutting down, until the point of failure (closed circuit) with no output.

Is ICS-5 a mis-typing of ICS-50? There is the spec of ICS-50 on
http://www.gws.com.tw/english/product/speed%20controller/50.htm,
please check. We do not recommend ICS-50 to handle Li-Po battery because ICS-50 is a 2A speed control. Depending on the capacity of your batteries, you might need a larger amperage speed control.

OTHER

1. For JST connector -- max. current around 7amp.
2. For A2 connector -- max. current around 12amp.
3. For A3 connector -- max. current around 15amp.

PC03 is a single axis Pass-Con unit instead of three axis gyro. Resolution and accuracy is following the performance of sensor installed in the gyro.

According to your description, we suggest you to find the reset point first and adjust the throttle and check reverse function as well. I enclose the speed controller instruction for your reference. If you still have question, please do not hesitate to contact us.

All GWS products under well quality control. The "J" is made for fit with JR radio. Since your Hitec is rather similar to FUTABA type. You should ask the shop to provide you a R4P "F" type. You'd better bring you TX & other airborne equipment to the shop, make sure every thing is fine.

Please be advised the absolute maximum value of "PICO F STD" is 8 micro second. We would suggest you to use 5 cell (6.0V) battery pack.

Model types and construction

Generally speaking, there are no clear definitions or differentiation.

Indoor Flyers: Indoor models are mostly the smallest, lightest and slowest. Typically they weigh under 8oz. Many indoor venues impose a maximum weight limit, often 150gm. Indoor models have very low wing loadings and use the smallest available cells 50 or 110mAh being fairly usual as well as specialised motors often coreless.

Slow Flyers: Slow Flyers are sometimes regarded as an in-between type, next level up form indoor models. Some people use "Slow Flyer" as an inclusive term covering both indoor models and park flyers. Basically small, light and slow enough not to need a standard club flying field.

Park Flyers: Generally, Park Flyers are too large or heavily loaded to fly indoors. They tend to use Speed 280 size motors and up, often geared and batteries up to about 600mAh. They can weigh anything up to 16-18 oz though they are often quite large and so still have very light wing loading. They are intended for use in relatively small outdoor areas such as schoolyards or local parks.

EDF stands for Electric Ducted Fan. Instead of driving a propeller the motor drives a multi-blade fan in a duct (tube) in the middle of the aircraft. GWS EDF models are scale or semi-scale jets, often military subjects though airliners and the like are also served for.

1. Above all, we have to apply the battery pack's mAh rating to decide how long the needed current can be delivered in minutes:
duration = 60 * (capacity/1000) / current
eg: to calculate the duration of a 1700 mAh pack for a 30 amp draw:
duration = 60 * 1.7ah / 30 amp
duration = 3.4 minutes.

2. we can get a rough but useful estimate by finding it on the ground and then multiplying by 0.75. If your propeller is highly pitched enough so that it is stalled when running static this number will be far less accurate.

AIRPLANE

Our Aero-modeling engineer said, it is about 40Km/hr ~ 60Km/hr normally.

1. Normally, it is about 15ft ~ 30 ft in height.
2. You can try to use 7N8.4V730mAh Ni-MH or 7N8.4V600mAh Ni-CD battery pack for better performance. If you'd like to put a 7N8.4V600mAh Ni-CD battery pack on A-10, please remember re-adjust the C.G. point of airplane because the Ni-CD is more heavy than Ni-MH.

Please kindly try to change it according to the following 3 steps as soon as you can, we are sure that you have well-experience in various models.
1. To use the knife cut the Horizontal Stabilizer away carefully. (Separate with the Fuselage)
2. From the backside of Cockpit to use the knife forward to the Vertical fin, then cut it away.
3. When the Fuselages had been separated, then you can adjust the bent Fuselage accordingly.
Lastly, you need to glue the Horizontal Stabilizer and re-painting it again.

That will be about 7A current draw, for 7.2v and 9070 prop on Estarter. But we do not recommend Estarter w/EPS-400C powered by 7.2v battery pack, 8.4v or 9.6v 750mAh battery pack with ICS300/ICS480 would be more appropriate. 7.2v and EP9070 do not give sufficient power to this airplane.

You can upgrade GWS A10-EDF50 to A10-EDF55 by buying bigger nacelles and EDF55 motors. The EDF55 upgrade pack is available now, you can call up local hobby store to buy one. But if you can wait a little while, GWS will announce new high voltage EDF50 duct fan unit in June. The high voltage EDF50 motors can be used on A10 with 9.6v battery pack which makes the airplane aerobatic.Retract for A-10 is too heavy. There is no need to make changes for using Futaba radios on GWS airplane. GWS produces both Futaba and JR compatible radios, servos and accessories.

Our engineer suggests that you can use the EP1060 propeller in EPS-400C power system for "E-Starter" airplane, kindly refer to further information at http://www.gws.com.tw/english/product/airfly/tm400.htm.

If you use the gear type D, it would be better to use EP1147. If you use gear type D with EP1080, then the power will not be enough for E-starter. The best combination will be EP1147 with gear type D and EP1080 with gear type C. The flying weight 350~450g is just a range for your reference. 400gr of your plane is at the normal range. It's included the weight of the battery.

We don't recommend EDP400, the power is not enough. If you would like to faster speed, please select GW/EPS-350C-AS/BB plus propeller 8060, battery 9.6V.

Yes, the GWS floats can used on EStarter-EPS350C and DHC2-EPS350C (Beaver), please see the attahced pictures for your reference.

If you choose A10 EDP series, the EM300H motor is the largest motor.

Except the Airplane kit, you still need:
1. 4ch transmitter & Tx crystal.
2. 4ch receiver & Rx crystal.
3. 3 pcs X PICO/NARO/MICRO/MINI servos
4. speed controller(GW/ICS-300 above)
5. Battery: 2/3 AA 270~400 mAH or AA600mAH/7.2V
6. Quick Charger

You are available to use a 9.6V 730mAH battery pack, and use EP9070 propeller. When your Zero on Flying, please do not control full speed for protecting your motor.

Please be advised that break-in the electric motor for Zero as below 1/3 throat 2 minutes and 1/2 throat 2 minutes.

The holes of the fuselage are quite normal situation. No need to worry about that. It wouldn't affect any flying performance. Our pilot suggest that you may use the stickers to cover it up if you think the appearance is not so good.

There is no such formula available. Mainly, the relation between thrust and weight is depended on the characters of the planes you have. Different planes may have totally different relation. Therefore, it's really hard to tell you a certain formula for determining the relation between them. In our opinion, the best way to find out that so far is to try equipping with different combination under your good knowledge of electric planes and to see which one works best. Of course, failure might happen when you are doing the try, so you better start with the similar equipment and then go further. Surely you can find a lot of fun out of it. If you are not very experienced, it's better just to follow the manual of your plane.

AIRPLANE ( DUCT FAN JETS)

It is about 40Km/hr ~ 60Km/hr normally.

The scale of A10 is 18:1 approximately.

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