Timer Settings (Torque Control Overcurrent) - ABB REL 301 Instruction Leaflet

I.L. 40-386.4
NOTE:
d. For Out-of-Step Block ("OS Block"), if applied, the Out-of-Step Block Override Timer Set-
ting ("OSOT") is determined by the power system operation. Its range is 400 to 4000 ms,
in 16 ms steps.
e. For the REL 302 blocking system only, the channel coordination timer setting ("Blk Time")
is based on the following application criteria:
"Blk Time" > (Slowest remote carrier start time + channel time + margin) - (the fastest local
21P/21NP pickup time)
Where channel time includes the transmitter and receiver times, and the times which occur
between these devices, e.g., wave propagation, interfacing relays, etc.
For REL 302:
fastest 21P/21NP pickup time
slowest carrier start time
suggested margin time
For example, the REL 302 channel coordination timer should be determined as shown be-
low, if the channel time is 3 ms.
"Blk Time" = (4 + 3 + 2) - 14
i.e., set "Blk Time"
3.2.8

Timer Settings (Torque Control Overcurrent)

Zone-2 timers, for phase and ground, can be set for a timed overcurrent delays. Zone-2 torque
controlled, time delay overcurrent ("T2Ø Type" and "T2G Type" set to "Torque Control") pro-
vides access to seven sets of overcurrent curves which are similar to ABB CO curves. Three
settings "T2Ø CV", "T2Ø PkUp" and "T2Ø TC" must be determined to apply phase torque
controlled overcurrent protection. Similar settings are required for the ground torque controlled
overcurrent protection.
a. "T2Ø CV" - Zone-2 phase overcurrent curve family setting. Seven sets (families) of CO
type overcurrent curves are provided and shown in Figures 2-32 through 2-38. As with any
overcurrent function, curve family selection is based on the application and coordination
with other overcurrent devices. Setting the family setting is by choosing CO-2, C0-5, CO-6,
CO-7, C0-8, CO-9 or CO-11. Each of the curve sets offers a choice of reset characteristic
which is explained below.
b. "T2Ø PkUp" - Zone-2 phase overcurrent pickup setting. In general, the pickup setting is
set above maximum load current and below maximum phase fault current. For maximum
sensitivity, the pickup should be set as close to maximum load current as possible. Pickup
setting range is 0.50 - 10.00 Amps.
c. "T2Ø TC" - Zone-2 phase overcurrent curve selection setting. This setting can also be re-
ferred to as the time dial setting. As shown in Figures 2-32 through 2-38, "T2Ø TC" is
settable in steps of one from 1 to 63. As with any overcurrent function, curve time dial is
based on the application and coordination with other overcurrent devices.
3-8
T3Ø Time and T3G Time are separate timers; they can have different time
settings if the application requires.
= 0
= 14 ms
= 4 ms
= 2 ms
= -5