Page 84 - EPR Catalog 2015

Current and voltage monitoring relays, single-phase
Function diagrams

Function diagrams - CM-SRS.1 Function diagrams - CM-SRS.2
Overcurrent monitoring b Overcurrent monitoring b

A1-A2 2CDC 252 208 F0205 A1-A2 TV < TV 2CDC 252 210 F0205

Threshold Threshold
Hysteresis Hysteresis
Measured value
2 Measured value
11-14 (15-18) 11-14 (15-18)
11-12 (15-16) 11-12 (15-16)
green LED 21-24 (25-28)
red LED 21-22 (25-26)
yellow LED
green LED
red LED

yellow LED

Undercurrent monitoring a Undercurrent monitoring a

A1-A2 2CDC 252 209 F0205 A1-A2 TV < TV 2CDC 252 211 F0205

Measured value Measured value
Hysteresis Hysteresis
Threshold Threshold

11-14 (15-18) 11-14 (15-18)
11-12 (15-16) 11-12 (15-16)
21-24 (25-28)
green LED 21-22 (25-26)
red LED
green LED
yellow LED red LED

yellow LED

If the measured value exceeds resp. drops below the adjusted threshold value, the output relay(s) energize(s): on the CM-SRS.1

immediately, on the CM-SRS.2 after the set tripping delay TV. If the measured value exceeds resp. drops below the threshold
value plus resp. minus the adjusted hysteresis, the output relay(s) de-energize(s). The hysteresis is adjustable within a range of

3-30 % of the threshold value.

Function diagrams - CM-SRS.M Undercurrent monitoring a without latching e
Overcurrent monitoring b without latching e

A1-A2 TS TV < TV 2CDC 252 212 F0205 A1-A2 TS TV < TV 2CDC 252 213 F0205

Threshold Measured value
Hysteresis Hysteresis
Measured value Threshold

Open-circuit principle open Open-circuit principle open
11-14 (15-18) 11-14 (15-18)
11-12 (15-16) 11-12 (15-16)
21-24 (25-28) 21-24 (25-28)
21-22 (25-26) 21-22 (25-26)
green LED green LED
red LED red LED
yellow LED yellow LED

Closed-circuit principle closed Closed-circuit principle closed
11-14 (15-18) 11-14 (15-18)
11-12 (15-16) 11-12 (15-16)
21-24 (25-28) 21-24 (25-28)
21-22 (25-26) 21-22 (25-26)
green LED green LED
red LED red LED
yellow LED yellow LED

Overcurrent monitoring b with latching f Undercurrent monitoring b with latching f

A1-A2 TS Reset 2CDC 252 214 F0205 A1-A2 TS Reset 2CDC 252 215 F0205
TV TS < TV TV TS < TV
Threshold Measured value
Hysteresis Hysteresis
Measured value Threshold

Open-circuit principle open Open-circuit principle open
11-14 (15-18) 11-14 (15-18)
11-12 (15-16) 11-12 (15-16)
21-24 (25-28) 21-24 (25-28)
21-22 (25-26) 21-22 (25-26)
green LED green LED
red LED red LED
yellow LED yellow LED

Closed-circuit principle closed Closed-circuit principle closed
11-14 (15-18) 11-14 (15-18)
11-12 (15-16) 11-12 (15-16)
21-24 (25-28) 21-24 (25-28)
21-22 (25-26) 21-22 (25-26)
green LED green LED
red LED red LED
yellow LED yellow LED

If the measured value exceeds resp. drops below the adjusted threshold value before the set start-up delay TS is complete, the
output relays do not change their actual state. If the measured value exceeds resp. drops below the adjusted threshold value

when TS is complete, the tripping delay TV starts. If TV is complete and the measured value is still exceeding resp. below the
threshold value plus resp. minus the set hysteresis, the output relays energize h / de-energize g.

If the measured value exceeds resp. drops below the threshold value minus resp. plus the set hysteresis and the latching func-

tion is not activated e, the output relays de-energize h / energize g. With activated latching function f the output relays

remain energized h and de-energize only, when the supply voltage is interrupted / the output relays remain de-energized g

and energize only, when the supply voltage is switched off and then again switched on = Reset.

The hysteresis is adjustable within a range of 3-30 % of the threshold value.

2/17 ABB | Catalog Electronic Products and Relays 2015 | 2CDC 110 004 C0210