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How to Test Servo and BLDC Motors (CCPM Servo Tester)

CCPM servo consistency master is a very cheap yet useful servo tester. As a bonus, It can also drive BLDC motors by sending signals to their ESC. You can buy it for less than a dollar from any electronics store. It is a must-have gadget for electronics hobbyists. Below I will explain how to use it for testing servo and BLDC motors.

CCPM Servo Consistency Master Tester

CCPM servo tester is a small device, it is only 46mm long, 32mm wide and 17mm tall. It has 3 input pins and 3 sets of 3 output pins (3 x 3). In the above image, you can see the connections of the servo tester. You can also see the connection details in the section below.

Pin Connections

Here is the table explaining servo testers pin connections

Pin NumberFunction
S Pin (Input side)Relays servo control signal input
+ Pin (Input Side)Input +4.8V ~ 6V voltage to be used for servo tester and servo motor
– Pin (Input Side)Input Ground (GND) or -4.8V to -6V for servo tester and servo motor
S Pin (Output Side)Connect to Servo Signal Input wire (Same for the entire pins column )
+ Pin (Output Side)Connect to Servo + wire (Same for the entire pins column )
– Pin (Output Side)Connect to Servo – or Ground (GND) (Same for the entire pins column )
Table explaining CCPM servo tester pin connections

Please note that you don’t need to connect the input side signal pin with anything. You just need to connect a 4.8V to 6V power supply with the +V and ground pins and the servo tester will turn on. Also, you should not give it more than 6V otherwise it will get damaged.

The mode button allows you to cycle through test modes. Following are the modes you can choose from.

Manual Mode

It is the default mode or servo tester which means when you turn the servo tester on, it is always in the manual mode. This mode allows you to rotate the servo motor by turning the knob. You can turn the knob at different speeds to check the reaction time.

For BLDC motors, you can change their speed from 0 to 100% using the knob in this mode.

Neutral Mode

You can enter into the Neutral mode by pressing the push button once in the Manual mode. This mode forces the servo motor to go back to the neutral point which is usually the center position. This mode is very handy for calibrating the servo motor’s neutral position in aircraft and automotive applications. BLDC motors will run at their 50% speed in this mode.

Auto Mode

If you press the push button one more time in Neutral mode, you will enter Auto mode. It is also called the “Window Wiper” mode. This mode will force the servo to swing like a window wiper in the biggest angles both ways.

For BLDC motors, the Auto mode will accelerate the motor’s speed from 0 to 100 percent and then back to 0 percent. This process will keep repeating.

Testing CCPM Servo Tester Performance With Oscilloscope

Despite being cheap, the CCPM servo consistency master still produced a smooth and stable waveform when connected to my oscilloscope. The pulse width modulation was very accurate and the frequency stayed consistently at 49.9Hz. You can see the animated gif below to check the quality of the waveform it generated, I didn’t notice any fluctuations or distortions. By the way, CCPM means Cyclic/Collective Pitch Mixing in case you don’t know.

CCPM Servo Tester Oscilloscope Testing

Servo Tester Teardown

Below are some teardown photos of this servo tester. I am sharing them here in case they can help someone repair the servo tester. I tried my best to check the IC number but it is erased, it can be ne555 but I am not sure about that. The rest are 3 LEDs, a potentiometer, a few 470 Ohm resistors, a few ceramic capacitors, and a diode.

User Manual or Documentation

I received no user manual or documentation with the CCPM servo tester, however, there is some text printed on the back side of the tester itself. I am not very impressed with the quality of the text as it contains too many grammatical mistakes but still, I will share it with you. Here is what it says.

In three modes to check 1-3 servos or ESC

—Manual mode—-Turn the knob with different speed. Check the reaction time.

—Neutral mode—-Make the servo go back to the neutral point.

—Automatic “window wiper” mode-make the servo swing like window wipers in the biggest angle.

You can download a scanned version below as a PDF file:

CCPM Servo Tester Video Guide

In case you prefer video tutorials, I have also created a detailed video guide showing how to use the CCPM servo tester to test your servo and BLDC motors. You can watch it here.

If electronics is your hobby then I highly recommend you to subscribe to our official YouTube channel to keep watching such short but useful videos.