Installation
The VXL-8s will install directly into most Traxxas models in the location of the
original speed control. The VXL-8s can also be installed in the chassis with double-
sided servo tape (part #1589, sold separately). When mounting the speed control
with double-sided servo tape, clean both application surfaces thoroughly with
alcohol. The surfaces must be perfectly clean for maximum adhesion.
Here are some tips for choosing a location for the speed control:
• Monitoring temperatures will extend the lives of the batteries, motor, and
speed control. To ensure the speed control does not enter premature thermal
shutdown, install it in a well-ventilated location that will provide adequate
airflow during use. The VXL-8s is equipped with
a cooling fan to assist in cooling
the speed control in high current motor applications.
• When mounting power components in a vehicle (wiring, motor, ESC), ensure that
none of the parts come into contact with any part of the radio system, particularly
the antenna wire. The receiver should be mounted so the antenna wire can be
extended as far away from the speed control as possible. The antenna wire should
be extended vertically in the mast and not wrapped on the chassis under the
body. Excess antenna wire should not be coiled on the chassis. Servo cables and
the antenna wire should not cross or come in contact with any of the motor or
battery wires. These steps will help reduce the possibility of radio interference.
• Mount the speed control where it will be protected from crash damage. Also,
protect the speed control from dirt and debris kicked up by the tires.
• Mount the speed control where you will have easy access to the plugs and the
on/off (EZ-Set®) button without having to remove the body.
VXL-8s Wiring
The VXL-8s electronic speed control is capable of controlling sensorless brushless
motors. The VXL-8s auto-detects the motor type and has numerous built-in
safeguards to prevent damage from miswiring or damaged wiring.
Sensorless brushless motors
Sensorless motors are the easiest and most reliable brushless motor type.
The VXL-8s is optimized to deliver the smoothest possible sensorless motor
performance. The Velineon 1200XL is a sensorless brushless motor. The wiring
(phase alignment) of the motor determines its direction of rotation. Refer to the
wiring diagram below.
Transmitter Setup
Traxxas TQi Radio Systems
Before attempting to program your VXL-8s, it is important to make sure your TQi
transmitter is properly adjusted (set back to the factory defaults). Otherwise, you
may not get the best performance from your speed control.
The transmitter should be adjusted as follows:
1. Set the throttle neutral switch to the 50/50 setting. This adjusts the
transmitter’s throttle trigger throw to 50% for throttle and 50% for braking and
reverse. Experienced users may wish to use the 70/30 setting if more broad
proportional control is desired in forward than with braking and reverse. This
might be desirable in a racing environment where reverse is disabled.
2. Set the throttle trim control to the middle 0 setting.
3. You are now ready to program your speed control.
Aftermarket (Non-Traxxas) Transmitters
The following instructions are provided as a general reference only for those who
are using non-Traxxas transmitters. Consult your transmitter’s instructions for
information on how to change the settings.
1. Set the High ATV (adjustable travel volume) or EPA (end point adjustment) to the
maximum setting. This is the amount of servo throw at full throttle.
2. Set the Low ATV, EPA or ATL (low side only trim adjustment) to the maximum
setting. This is the amount of servo throw at full brakes or reverse.
3. Set the throttle trim to the middle (neutral setting).
4. Set the throttle channel reversing switch to either position. Do not change the
switch position after programming.
5. Set the trigger throw adjustment to 50% throttle and 50% brake (either
mechanical or electronic).
6. Set the exponential setting (if equipped) to the zero or fully linear setting.
Aftermarket Receivers
The VXL-8s is compatible with most aftermarket receivers.
By removing the tab on the edge of the power connector,
the VXL-8s can be plugged directly into some models of
Futaba®, Airtronics®, Hitec®, and JR® receivers. Please refer to the
manufacturer’s wiring diagrams that came with your receiver.
On the VXL-8s, the red wire is positive, the black wire is negative, and the white wire
is the control wire.
WARNING:
On some older Airtronics® radio systems, the positive
and negative terminals are opposite of the VXL-8s and an adapter is required.
Crossing the red (+) and black (-) wires could damage the receiver and the VXL-8s.
Study the manufacturer’s wiring diagrams closely, or consult your hobby dealer.
Low Voltage Detection
The VXL-8s electronic speed control is designed to operate on 4S, 6S, or 8S LiPo
battery power and
is equipped with built-in
two-stage Low Voltage Detection.
The Low Voltage Detection circuitry
constantly monitors the battery voltage
and
alerts the driver when LiPo batteries have reached their minimum voltage
(discharge) threshold. It is the driver’s responsibility to stop immediately to
prevent the battery pack from being discharged below its safe minimum
threshold. When you turn your model on, the speed control’s status LED is green,
indicating that Low Voltage Detection is activated.
DO NOT use NiMH batteries with the
VXL-8s electronic speed control. The
batteries will become extremely hot
and damage or injury could occur.
VXL-8s Setup Programming
(Calibrating your ESC and transmitter)
Read through all of the programming steps before you begin. If you get lost
during programming or receive unexpected results, simply unplug the battery,
wait a few seconds, plug the battery back in, and start over.
1. Connect two fully charged battery packs to the VXL-8s.
2. Turn on the transmitter (with the throttle at neutral).
3. Press and hold the EZ-Set button (A). The LED will first turn
green and then red. Release the EZ-Set button.
4. When the LED blinks RED ONCE, pull the
throttle trigger to the full throttle position
and hold it there (B).
5. When the LED blinks RED TWICE, push the throttle
trigger to the full reverse and hold it there (C).
6. When the LED blinks GREEN ONCE, programming is
complete. The LED will then shine green, indicating
the VXL-8s is on and at neutral.
VXL-8s Operation
To operate the speed control and test programming, place the vehicle on a stable
block or stand so that all of the drive wheels are off the ground. Disconnect motor
wires A and C, this will assure the motor does not drive the wheels during testing.
Do not test programming without disconnecting the motor wires.
Note that in
steps 1-7 below, Low Voltage Detection is ACTIVATED (factory default) and the LED
shines green.
1. With the transmitter on, press and release the EZ-Set button. The LED will shine
green. This turns the VXL-8s on.
2. Apply forward throttle. The LED will turn off until full throttle power is reached.
At full throttle, the LED will illuminate green.
3. Move the trigger forward to apply the brakes. Note that braking control is fully
proportional. The LED will turn off until full braking power is reached. At full
brakes, the LED will illuminate green.
4. Return the throttle trigger to neutral. The LED will shine green.
5. Move the throttle trigger forward again to engage reverse (Profile #1). The LED
will turn off. Once full reverse power is reached, the LED will illuminate green.
6. Return the throttle trigger to neutral. (
Note:
There is programmed delay when
changing from reverse to forward. This prevents damage to the transmission on
high-traction surfaces.)
7. To turn the VXL-8s off, press the EZ-Set button until the LED turns off (0.5
seconds).
VXL-8s Profile Selection
The speed control is factory set to Profile #1 (100% forward, brakes, and reverse).
To disable reverse (Profile #2) or to allow 50% forward and 50% reverse (Profile
#3), follow the steps below. The speed control should be connected to the
receiver and battery, and the transmitter should be adjusted as described
previously. The profiles are selected by entering the programming mode.
Profile Description
Profile #1 (Sport Mode): 100% Forward, 100% Brakes, 100% Reverse
Profile #2 (Race Mode): 100% Forward, 100% Brakes, No Reverse
Profile #3 (Training Mode*): 50% Forward, 100% Brakes, 50% Reverse
VXL-8s
+ Positive
- Negative
A (Blue)
B (Black)
C (White)
+ Positive
- Negative
A (Blue)
B (Black)
C (White)
VXL-8s
Motor
Green then Red
A
Once Red
B
Twice Red
C