Rockwell Automation 1395 Digital DC Drive FRN 5-10.10/9.30 - Manual (Page 80)

Chapter 4
Hardware Description
125 – 300 HP, 230VAC 250 – 600 HP, 460VAC
4-16
Relay Logic Main Contactor (M1) Control – Figure 4.13 illustrates the hardware
associated with the control of the coil voltage applied to the Main DC
contactor M1. The coil voltage originates at an external 115VAC source.
The source voltage may be interrupted before being input to the Drive at
TB5-6 by the use of externally controlled contacts. These external contacts
may include an external master coast stop contact, PLC controlled
contacts, permissive contacts, etc. These contacts are illustrated
as“external control contacts”. Main contactor M1 coil voltage is
controlled within the 1395 through the pilot relay (PR) contacts.
Auxilliary contacts on M1 send 115VAC to the Power Stage Interface
when M1 is energized. This signal is rectified and optically isolated to
produce a 5V logic signal CVERIFY which is sent to the Main Control
Board.
Pilot Relay (PR) Control – K2 and K3 contacts in series with the
115VAC Coast Stop input to the drive control coil voltage to the Pilot
Relay.
ECOAST Stop – The “ECOAST STOP” as defined and illustrated, is a
contingency circuit designed to stop the motor in the event of a
malfunction in the solid state interface drive software.
When an ECOAST Stop is initiated, the DC loop contactor is de-energized
and the motor will coast to a stop.
Relay K2 on the Power Stage Interface is the ECOAST stop relay and is
controlled by +24VDC. As shown in Figure 4.13, +24VDC from the
Power Stage Interface is connected to TB3-12 and 11. At this point, an
external 24VDC ECOAST stop contact could be used to control the
application of 24VDC to K2 through TB3-9. TB3-12 and 10 should
always be jumpered together to provide a return path for 24VDC. If an
external 24 VDC ECOAST stop contact is not used, then TB3-9 and 11
must be jumpered.
In addition to the 24VDC ECOAST stop, there is a 115VAC ECOAST stop
circuit which is provided as standard in the 1395. 115VAC enters the
Power Stage Interface from TB6 and is distributed to TB3-4. Between
TB3-4 and 5, an external ECOAST stop contact may be connected. If an
external 115VAC ECOAST stop circuit is not used, TB3-4 and 5 must be
jumpered. 115VAC is returned to the Power Stage Interface from TB3-5
and sent to the contacts K2. From here it proceeds to the contacts of K3 on
the Power Stage Interface. The 115VAC ECOAST stop signal is also sent
to an isolation circuit which converts the 115VAC to a +5VDC control
signal ECOAST which is sent to the Main Control Board.
Main Control Relay – K3 on the Power Stage Interface is the main
control relay which controls turn on voltage to the coil of the pilot relay
PR. K3 is controlled by logic signals from the Main Control board
entering the Power Stage Interface through ribbon connector J9. The two
signals which control K3 are the SYSTRIP and the DCPILOT signals. In
order for K3 to cause PR to be energized, there must be no system fault
and there must be a DC pilot relay turn on command. If both these
conditions are met, K3 is energized, and PR is in turn energized. The
control voltage being applied to K3 may be monitored on the Power Stage
Interface at TP2. If K3 is being commanded to energize, the voltage at TP2
will be 0VDC. If K3 is to be de-energized, the voltage at TP2 will be
+24VDC.