What NOT to do with the QCM:
Do not use QCM to measure your aircrafts fully amperage load. There are other devices on the market that will work for that. The QCM is designed for a single servo on each channel. Not a battery on channel and plane on the other end.
Since the QCM is a new product I am sure there will be more for this section later.
Tips and Tricks:
ISOLATE YOUR WORK:
When hooking up your QCM, if at all possible try to isolate the surface you are testing for binding, or are trying to match up. In other words if you are going to test your Right Aileron, you will want to disconnect all other surfaces from you RX before you plug in your Right Aileron. All testing should be done this way.
REASON: Since the sticks on our transmitters do more than one thing, (Throttle/Rudder)-(Elevator/Aileron) it is very easy to bump one surface while trying to test another just in moving the stick around. When this happens you are causing a voltage jolt (spike/fluctuation) on your RX buss, which in turn will cause a spike to go through the QCM. This will not hurt the QCM, however it can make it hard to read. If you are fine with that explanation skip the next paragraph,,, (I would!)
CAUTION: Calculation Ahead>
If your Servo is drawing 1.1 amps (I ) at a voltage of 8.4 (V ), the wattage will be 9.24 (P ) or ( I x V = P ).... Now lets say you have your whole plane 40% wired up and you are trying to test your Right Aileron, you have a Gang of 4 8711's on your Rudder that you keep bumping. When you bump that rudder stick you notice that your right Aileron numbers go crazy. What is happing when you do this is? You are messen with (V ) which will change the equation, and will show up in elevated Amperage readings. So in the first equation we figured out that the 8711 was using 9.24 watts (P ) to maintain its position. When you bump your rudder system you are dropping the Voltage of the buss to 7.6volts (V ). Now we must work the equation backwards ( P / V = I ) or 9.24(P ) / 7.6(V ) = 1.2(I ) . As you can see we have gained .1 or 100mA's just from a spike on the buss. This is why we recommend that you Isolate what you are testing.
ONE AT A TIME:
When hooking up your QCM try to land your Servo leads one at a time. Meaning Start on Servo#1, observe the reading, now plug in Servo#2 etc. This will allow you to make adjustments as you go along. You can plug everything in all at once (Let-her Rip Mode), however doing it this way can make it hard to figure out exactly which Servo that is causing the binding. Remember in a Gang of 4, 1 Servo can cause all the Servos to buzz and draw excessive current. Eventually you will get thing sorted out doing it this way, however it is not optimal and we suggest you do it one at a time.
One question we get a lot at Fromeco is, "Why is there an option for more than 1 JR™ out put lead on a Sahara?".
The standard hobby out put lead is not the most optimal connection. Due to their size and connection method, they can and do often induce resistance into your flight system.
We build the Sahara regulator to handle Amass in and Amass out. However many pilots due to set up constraints go straight from their Regulators right into their receivers. (this is not a bad thing) Often this set up is a Amass from battery, to switch, to regulator. However once you hit the receiver something must be done to actually get the power into the RX. In most cases Amass can not be used. **This gives you a Sahara with Amass in and a JR™ out.
Now for the Explanation:
Many of you may have heard me on the phone giving the Fire Hose Garden Hose analogy.
Which goes like this, if you take a Fire Hose and Hook a Garden Hose to the end of it, you will only get the maximum water flow of the Garden Hose, or realistically the Garden hose will explode, but you get my point.
Doubling or even tripling the JR™ out put lead on the Sahara reduces the resistance of the JR™by either 1/2, or if you have 3, 1/3. It also doubles or triples the rated amperage flow, this is essentially a factor of less resistance. When you have a high flow, low resistance system (Amass 16awg wire), and you add a JR™ connection you are basically doing the Fire Hose to Garden Hose deal. The goal with multiple out puts is to get as many Garden Hoses on the Fire Hose as possible.
Where does the 2nd or 3rd JR™ connector go? Any Open Port on your Receiver.
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