S3 Digital Inputs - GE 469 Instruction Manual

5.4

S3 Digital Inputs

5.4.1 Description
5–26
Overview
The 469 relay has nine (9) digital inputs. Five of the digital inputs have been pre-assigned
as switches having a specific function. Four of the five pre-assigned digital inputs are
always functional and do not have any settings messages associated with them. The fifth,
Starter Status, may be configured for either an 'a' or 'b' auxiliary contact. The remaining
four digital inputs are assignable; that is to say, the function that the input is used for may
be chosen from one of a number of different functions. Some of those functions are very
specific, others may be programmed to adapt to the user requirements. If the Two-Speed
Motor feature is enabled, Assignable Input 4 will be dedicated as the Two-Speed Motor
Monitor.
Access Switch
Terminals C1 and C2 must be shorted to allow changing of any settings values. This
safeguard is in addition to the settings passcode feature, which functions independently
(see Passcode on page 5–8).
Test Switch
Once the 469 is in service, it may be tested from time to time as part of a regular
maintenance schedule. The relay will have accumulated statistical information relating
historically to starter and motor operation. This information includes: last trip data,
demand data (if the metering features are in use), MWh and Mvarh metering, RTD
maximums, the event record, analog input minimums and maximums, number of motor
trips, number of trips by type, total motor running hours, learned parameters, number of
starter operations, number of motor starts, number of emergency restarts, and the digital
counter. Shorting the 469 Test input (terminals C3 and C4) prevents all of this data from
being corrupted or updated when the relay is under test. The In Service LED will flash while
the test terminals are shorted.
Emergency Restart
Shorting terminals D17 and D23 discharges the thermal capacity used to zero, sets any
Starts/Hour Block lockout to zero, sets any Time Between Starts Block lockout to zero, and
reset all Trips and Alarms so that a hot motor may be restarted. However, a Restart Block
lockout will remain active (it may be used as a backspin timer) and any trip condition that
remains (such as a hot RTD) will still cause a trip. Therefore, while the terminals are shorted,
the Trip and Block output relays will remain in their normal non-operated state. In the
event of a real emergency, the Emergency Restart terminals should remain shorted until
the emergency is over. Also, while the Emergency Restart terminals are shorted, a Service
Alarm message indicates any trips or blocks that are active. As the name implies, this
feature should only be used in an emergency – using it otherwise defeats the purpose of
the relay, namely, protecting the motor. Any Emergency Restart input transition from open
to closed or closed to open is logged as an event.
CHAPTER 5: SETTINGS
469 MOTOR MANAGEMENT RELAY – INSTRUCTION MANUAL