Wiring a basic radio system to the A15 ESC
This is a typical Speed 400 power system. Click here to see a step by step gearbox assembly. There are a couple of details this picture should help with. The first one is the fuse setup. It is our recommendation to use a fuse of an appropriate amperage rating for the system you will be using, in this case a geared 400 size motor is spinning an 8-inch prop and testing with an amp meter showed that it would draw about 6 amps. This fuse is an automotive spade fuse of the 10 amp range and it will blow in plenty of time to save the controller. This fuse works very well with a couple of typical automotive spade lugs that will slide on the each leg of the fuse and will allow a quick change if needed (remember to shut the throttle off if you think your plane is coming down). Crimp or solder them to the positive lead between the motor and the ESC and insulate them with a short length of shrink tubing (black sleeve pictured below the fuse). The next noteworthy thing is the noise suppression capacitor. That is the little brown disc pictured between the motor and the battery. Most of our motors have internal capacitors and some come with an external one to solder between the motor terminals at the time you solder the power leads to the motor. The capacitors job is to short out the radio frequency signals that an electric motor normally emits as it runs. When installing the cap, keep the leads as short as possible and use a tiny piece of shrink tubing to keep the legs of the capacitor from shorting to the motor. Suppressing a motor this way should eliminate receiver glitching. Lastly, notice that we use Sermos connectors to hook up the battery. You can use any type of connector you are comfortable with but since we supply this type, I will outline how they are used with a couple extra pictures.
Sermos (or Anderson Power Poles) are capable of handling lots of power and they slide together easily. They can be tricky to figure out if you have never worked with them before. Study the pictures carefully and notice how the shells and lugs are set on the table. This is the only way the lug will fit into the shell. Look in the back of the shell and you will see an off-set slot, this is what the lug will slide through then click onto a metal retainer. The hook on the front of the lug will snap thoroughly onto that retainer and can only be removed by lifting the front of the lug with a tiny pick or strong "darning" needle while pulling on the wire. Sermos should always be soldered to the wire. Strip about 1/4-inch insulation off the wire and if the wire is small compared to the lug, go ahead and tin the wire with solder before inserting it into the lug. If the wire is heavy gauge it probably won't fit if it is tinned so insert it then solder it. Place the tip of the soldering iron on the closed end of the lug and feed the solder into the back where the wire goes in. keep the heat on the lug until it draws in the solder from the back and feed enough solder in to fill the lug. If solder is clumped up on the outside of the lug you will need to sand or file it off because the lug will not fit into the shell. A good customer tip was to scrub the lug with steel wool or wash the lug with thinner to remove the flux as it could impair the power transfer. After the wire is soldered on and cooled, push the lug into the back of the shell making sure it is lined up exactly like the picture above. You may have to use a tiny screwdriver to push on the back of the lug until you here a click that indicates it is in place. Sermos can be configured a number of ways including a way that will let you hook them up in a reverse polarity that will thoroughly destroy your speed control and possibly the receiver! The left picture shows the plug shells being hooked together. Notice that each shell has a channel on two sides and a raised portion on two sides. The raised bump will slide into the channel on the adjacent one. I start with the speed control and configure that set of plugs then, after the batteries are soldered to the connectors, configure the battery plugs to match and slide them together. If done correctly, it will be impossible to reverse the polarity of the battery.
This
wiring diagram should be helpful if you are setting up our Tetra FM micro
receivers or your own OEM receivers with our FMA servos and various speed
controls. First and
foremost, you will have to determine the how the pins are wired on the plug
block of your receiver. The easiest way is to plug in an OEM servo and power
plug and observe the positions of the black (-), red (+), and signal (usually
white). Most, but not all, servo and power plugs are arranged with the red (+)
in the middle and black and white on either side. Older Airtronics
radios do not follow this convention and swap the wires around, so if you
have that system – be sure to check it closely and change the plug wiring
order as necessary. Futaba, JR and Hitec are generally interchangeable but you
will have to shave the tab key off the Futaba plug and file a bevel on two edges
to use it in JR and Hitec radios. If you modify any plugs, you will then have to
be very careful to get polarity correct when plugging in because, with no key,
they can turned around. We sell Hitec radio system here and they can be set up
the same way. On the Hitec receivers, all the black plug leads from servos and
BEC speed controllers are lined up along the outside edge of the plug block. The
power plug from the A20 will go to the B or Battery slot and the Power /
Throttle plug from the SC20 will go to the throttle channel.
The
wiring diagrams above are self explanatory with a few additional notes. The best
way I remember how the plugs hook up to the Tetra receiver is to use a black
permanent ink marker and draw a black line along the plug block on the component
side of the circuit board. Line up all the black wires (negative) on all power
and servo plugs along that side. Be careful! It is very easy, especially for us
who are getting far sighted, to hook a servo up with the plug shifted one pin up
or down, missing one of the pins on the plug block. This will fry a servo or
probably ruin a speed control too. If you are flying gas and using a standard
flight battery, you can hook the power plug from the switch to any channel on
the Tetra plug block not being used. The Tetra is a six channel receiver so you
may ask “how do I use the sixth channel if the battery is plugged into
it?!?!” That’s easy, simply use a Y-connector and hook one side of the Y to
the servo and the other side to the battery then plug the loose end into the
channel you want that servo on. The Tetra FM has a set of dip switches to match
the receiver with you transmitter. Use a needle to poke through the shrink wrap
and flip the levers according to the instructions included with the Tetra. The
FM will not work with PCM type radios.
One
of our
favorite controls is the Aveox A15 for speed 400 systems.
The A15 comes with Futaba plugs and will need to have the key tab shaved
off if you are using other radio systems. If you have a spare plug shell lying
around that fits your system, you can pull the wires out by using a needle to
lift the tiny tab holding the pin in the shell and then pop it into the other
plug shell, being careful of the wire positions. On the A20, the plug with three
wires (black, red, white) is the throttle plug and will hook to the throttle
channel. The plug with two wires (red, black) is the power from the BEC and can
hook to any channel on the Tetra or the Battery channel on other receivers.
The heavy Blue and Red wires go to the motor and should have a fuse
installed between the motor and the speed control in the red wire. For speed
400, a 10 amp fuse should be adequate but check your amp draw to be sure. DO NOT
GOOF and hook the red and blue wires to a battery or you will blow the speed
control up. The heavy red and black wires will get some sort of plug, we
recommend Sermos, to make connecting and un-connecting the power battery easy.
Again, DO NOT GOOF and reverse the polarity or you will blow the speed control!
Remember red is positive and black is negative!!