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RTT DESKTOP TEST SET– INSTRUCTION MANUAL
THE 239 MOTOR MANAGEMENT RELAY
CHAPTER 4: MOTOR MANAGEMENT & METERING
4.2.2
239 Motor Management Relay Terminal Layout
FIGURE 4–10: SR239 Relay - Rear View - Terminal Layout
4.2.3
239 Motor Management Relay Terminal Functions
FIGURE 4–11: SR239 Relay - Terminal Functions Schematic
819790AH-X3.CDR
COMMUNICATIONS
RS485 serial communications, 1200-19200 baud for
remote monitoring, setpoint programming, and
commands. Modbus RTU protocol.
®
SWITCH INPUTS
Enable/disable setpoint programming.
ACCESS:
Over-rides lockout for process restarting.
RESTART:
Field reset after a trip.
RESET:
User specified inputs.
OPTION 1&2:
OPTIONAL ANALOG OUTPUT
Select output as: thermal capacity used, current as a % of
full load, average current, RTD 1-3 temperature. Isolated
4-20 mA for PLC process input or 0-1 mA for thermal
capacity meter.
CUSTOMER ACCESSIBLE FUSE
Door slides open for easy access
to fuse.
AC/DC CONTROL POWER
Universal control power
90-300 VDC/70-265 VAC.
GROUND CT INPUT
5A or 50:0.025 CT input for
residually connected phase CTs
or separate core balance CT.
PHASE CT INPUTS:
3 isolated phase CT inputs.
Accept 1 amp or 5 amp secondary.
TEMPERATURE SENSING
NTC or PTC thermistor input.
OPTIONAL 3 RTD INPUTS
Mix RTD types. Separate stator and bearing monitoring
OPTIONAL DIRECTIONAL GROUND SENSING
Polarizing voltage input for directional ground sensing
(MOD 509)
4 RELAYS
Cause motor to trip by opening contactor
or energizing breaker trip coil.
TRIP:
Signals an alarm is present.
ALARM:
Programmable for control or separate trip/alarm.
Serial port commands for remote control.
AUXILIARY:
Signals internal relay fault.
Service is required.
SERVICE: