BOOK 0958-B
4.MOTOR CONTACTOR - Controller model numbers with an ‘A’ or ‘B’ suffix, e.g., 2331A, 2331AP0, have a DC magnetic armature contactor, which disconnects both motor armature leads from the controller. An antiplug circuit ensures that the contactor does not make or break DC.
5.POWER CONVERSION - The DC power bridge consists of four SCR’s, one freewheeling diode. Each device is rated at least 600 PIV. The controller base forms an integral heat sink, with the power devices electrically isolated from the base.
6.SELECTABLE CAPABILITIES - Switches allow the user to select various modes of operation, as follows:
a. LINE STARTING - By placing SW3:5 in the OFF position, the
b. TACHOMETER FEEDBACK - To use tachometer feedback with armature feedback backup, connect the tachometer generator signal to
TABLE 13. TACHOMETER FEEDBACK VOLTAGE SELECTION
TACH VOLTAGE | SW3:1 |
|
|
8Vdc - 30Vdc | ON |
31Vdc - 175 Vdc | OFF |
|
|
c. TORQUE REGULATOR - The controller will function as a torque regulator when SW3:3 is OFF. This allows an external potentiometer to set maximum motor torque (0 - 150% of rated).
7.VOLTAGE TRANSIENT PROTECTION - A metal oxide suppressor (varistor) across the AC line is combined with RC snubbers across the power bridge to limit potentially damaging high voltage spikes from the AC power source.
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