H2W Technologies LCAM 5/15 Operation & Service Manual - page 12
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-0540
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C. Calibration of the Current Mode Amplifier (LCAM 5/15 Series):
The amplifier in this configuration, receives an analog, bi-polar input command which is
proportional to the required motor current (motor torque). The following potentiometers (pots) will
be set during calibration: (Note: RV6 is a single turn pot and RV1-RV5 are 10-turn pots.)
PROCEDURE:
1. Apply main power and fan power. Visually confirm a green LED. Depending on the configura-
tion of the Inhibit, Reset and +/-Limits, it may be necessary to make appropriate connections
to those terminals before the amplifier will be enabled and energize the motor.
2. Slowly turn the Loop Gain (RV6) pot CW fully. The Motor should be stopped or turning slowly.
Set the Balance (RV2) for 0V at J1-7 (MTR I).
3. Install a micro-shunt at J3 connector (across J3-1 to J3-2).
Note: For single-ended signal input amplifier, a micro-shunt is permanently installed at J3
connector. On the other hand, the micro-shunt should be removed for differential input amplifi-
er after the calibration process.
4. Connect an oscilloscope to J1-7 (MTR I) and a battery box to J1-1 (J1-4 is common for both).
The voltage on J1-7 is a function of motor current: 1V = 2.0A. While applying a step input
voltage, adjust the Current Limit (RV5) for the desired peak current. If the desired peak
current cannot be achieved with the Current Limit pot full CW, increase the input Signal Gain
(RV1) by turning in the CW direction.
5. With the battery box still connected at J1-1 and J1-4 for single-ended input (or if your system
uses the Differential input, move battery box to J1-1 and J1-2, and remove micro-shunt at J3
connector), set the battery box for a known DC voltage. Apply ±input signal pulses and adjust
the Signal Gain pot (RV1) to obtain the desired current gain of the amplifier.
6. If the motor is rotating in the wrong direction for a given input polarity, remove the power and
reverse the motor leads.
7. Remove the battery box, and repeat step 2.
8. Calibration complete. Reconnect signal wires.
Pots
Name of Pot
Notes
RV1
Signal Gain, SIG
Sets the input voltage to velocity ratio for signal input.
RV4
Tach Gain, TACH
Sets the DC tachometer gain.
RV6
Loop Gain,
LOOP GAIN
Used to shut off uncalibrated amplifiers. When the loop gain is
fully CCW, no current is delivered to the motor.
RV2
Balance, BAL
Used to null any offset in system.
RV3 Compensation, COMP Used in conjunction with tach. gain to set the system bandwidth.
RV5 Current Limit, I LIMIT Sets the maximum motor current. Shipped set CCW (min. current).