MVAX 12_21_31_91 Brochure0 pages

PROTECTION PRODUCT SOLUTIONS

MVAX12/21/31/91

Trip circuit supervision relays

MVAX relays supervise the Simple and TObllSt

trip circuit of a circuit

breaker, initiating audible Four types are available providing the following supervision:

alarms and visual

RELAY TYPE FAULTS DETECTED

indications if the trip Circuit MVAXl2 " Failure of trip supply only

fails or the mechanism does MVAX2I Failure of trip supply

Y nnnnto MVAX 31 Open circuit trip coil, or trip circuit wiring failure of circuit breaker

P & MVAX 91 tripping mechanism

*MVAX 91 = 3 X MVAX 31

MVAX 31 provides supervision with the circuit breaker in either state

MVAX 21 with the circuit breaker closed only. If required, the alarm units of types

MVAX 21 and MVAX 31 can be operated via pilot wires.

MVAX 91 consists of three separate MVAX 3l's in a size 8 (40TE) case.

The relays are attracted armature units of simple and robust construction having a

positive action without chatter.

CUSTOMER BENEFITS

• Trip circuit can be supervised

with breaker open or closed

• No mis-tripping of breaker

by accidental short-circuits

• No false alarms given due to

protection operation

• Ensures the integrity of the

protection scheme

Grid-SAS-L3-MVAX_12-91-2515-2013_05-EN. Information contained in this document is indicative only. No representation or warranty is given or should be

relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided

without liability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

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