Rapid-Air PALLET MASTER (PMD) HIGH SPEED: 35, 50 & 100 SERIES User Manual

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Regen Run-Brake Switch
The Regen Run-Brake switch is optional. When the switch is in the open position, the motor
will run. When the switch is closed, the motor will be regeneratively braked to a stop. NOTE:
The Run/Brake switch acts as an inhibit function and will not unlatch the Start/Stop pushbutton
circuit.

Tachogenerator Feedback
Tachogenerator feedback is optional. Without tachogenerator feedback, load regulation is ap-
proximately 8% of base speed with a speed range of 10 to 1. This is quite acceptable for most
applications which do not involve sizable load changes. With tachogenerator feedback, load
regulation is better than 0.5% of base speed with a speed range of 30 to 1.

1. Clip resistors R5 and R6 from the lower board.
2. The control factory set for a tachogenerator rated at 50 volts per 1000 RPM, with a maxi-

mum motor speed of 1800 RPM. If the tachogenerator output is other than 50 volts per
1000 RPM, or the maximum speed of the motor is greater than 1800 RPM, calculate the
value of R1 based upon V max - the tachogenerator output voltage at maximum motor
speed. Note that V max must be at greater than 5 volts.

R1 = [(V/RPM)(RPM max)-5]+2.3, kohms
Where
V/RPM = Tachogenerator volts per rpm, and
RPM max = Maximum tachogenerator speed in the application

Select a standard 1/4 watt resistor of the calculated value and insert it into the two terminal
blaco TB# on the upper circuit board. If the calculated value is not available, select the next
higher standard resistance and, after steps 3 and 4 have been followed, use the Max Speed Ad-
just trim pot to set the maximum speed.

3. Set IR Comp trim pot fully CCW.

4. Connect the tachogenerator leads to terminal 1 (negative) and terminal 2 (positive). Tacho-

generator polarity is that produced with motor running in the FORWARD direction.

If any doubt exists concerning the tachogenerator polarity, start the motor very slowly. A mis-
wired tachogenerator will cause the motor to accelerate to full speed. If this occurs, disconnect
the control from the AC power immediately. Interchange the connections at terminal 1 and 2.
Reconnect AC power to the control and recheck.