GE MVAX31S1DE0754A — the MVAX31 trip circuit supervision relay, configured for 110/125 V service with hand-reset flag indication — is now held in stock at our Dubai facility for immediate dispatch. Across DEWA, ADDC, SEWA and EWEC substations, MVAX relays have been supervising trip circuits for four decades. When one needs replacing, the exact order code matters, and we can confirm it before you buy.

نظرة عامة: المرحّل GE MVAX31S1DE0754A هو مرحّل مراقبة دائرة الفصل (Trip Circuit Supervision) من عائلة MVAX، يراقب سلامة دائرة فصل القاطع في كلتا الحالتين — مفتوح أو مغلق. متوفر الآن في مخزوننا بدبي.

The Problem MVAX31 Was Built to Solve

A protection scheme is only as good as its ability to actually open the breaker. If the trip coil circuit develops an open circuit, a loose termination, or loses its DC supply, the protection relay will still operate correctly — and nothing will happen. The fault is silent and invisible until the day it matters.

Trip circuit supervision relays pass a small monitoring current through the trip coil circuit and raise an alarm the moment continuity is lost. The GE MVAX31S1DE0754A does this with the circuit breaker in either state.

That distinction is the entire reason MVAX31 exists. The simpler MVAX21 supervises only when the breaker is closed. MVAX31 adds a third unit, RL3, energised through the breaker’s normally closed auxiliary switch, so a trip circuit defect is detected while the breaker is open and before it is reclosed — pre-closing supervision. On a feeder that sits open for weeks, that is the difference between finding a defect during normal operation and discovering it during a fault.

Internally the relay comprises three units. With the breaker closed, RL2 and RL1 are energised. With the breaker open, RL3 is energised and holds RL1 in through contact RL3–1. Loss of continuity in any state drops RL1, operating the alarm contacts and the flag.

 

Order Code Decoded — MVAX31S1DE0754A

Most suppliers list this part number without explaining it. Here is exactly what you are buying:

Position	Code	Meaning
1–6	MVAX31	Trip circuit supervision relay with preclosing supervision
7	S	Size 3 case, grey/grey livery
8	1	Flush mounting
9	D	Hand-reset reverse flag indicator
10	E	1 make and 2 break standard output contacts
11–14	0754	DC supply (0000) + RL1 at 110/125 V (0750) + RL2 & RL3 at 110/125 V (0004)
15	A	Design/issue suffix

Reference tables for cross-checking your own units:

• Flag: A none · C self-reset reverse flag · D hand-reset reverse flag
• Contacts: C 3 make · D 2 make + 1 break · E 1 make + 2 break · F 3 break
• Supply: 0000 DC · 5000 AC 50 Hz · 6000 AC 60 Hz
• RL1 voltage: 0000 24/27 V · 0250 30/34 V · 0500 48/54 V · 0750 110/125 V · 1000 220/250 V DC
• RL2 & RL3 voltage: 0001 24/27 V · 0002 30/34 V · 0003 48/54 V · 0004 110/125 V · 0005 220/250 V

Note that 9xxx codes denote pre-defined variants incorporating a circuit-breaker closure inhibit contact. If your existing relay carries a 9xxx code, it is not interchangeable with 0754. Send us a photograph of the relay label and we will confirm the correct build in writing before you order.

 

Key Specifications | المواصفات الرئيسية

Parameter	GE MVAX31S1DE0754A
Type	MVAX31 trip circuit supervision relay, preclosing supervision
Supervision coverage	Circuit breaker open and closed
Internal units	RL1, RL2, RL3
Case	Size 3, flush mounting
Flag	Hand-reset reverse flag
Output contacts	1 make, 2 break
Supply	DC
Nominal voltage	110/125 V (RL1, RL2, RL3)
External resistor (Rext)	7400 Ω for 110/125 V service (3100 Ω for 48/54 V)
Voltage withstand	Full operative range continuously
Drop-off	Units slugged to prevent maloperation during transitions
Maintenance	No periodic maintenance required; inspection and test recommended at 12-month intervals
Technical manual	GE Grid Solutions R8010RB
Common scheme designation	74TC

 

Core Competitive Advantages

1. Supervision in both breaker states. The defining capability of over MVAX21. Defects on open feeders are found before reclosing, not after.

2. Electromechanical simplicity. No firmware, no configuration file, no settings to lose. The relay does one job and does it without a commissioning engineer and a laptop.

3. Proven over four decades. The MVAX range launched in 1983 with well over a quarter of a million units shipped. In GCC substations it is one of the most widely installed auxiliary relays in service.

4. Hand-reset flag preserves the evidence. The D flag option means the indication stays until a person clears it — the operator cannot miss a transient trip-circuit defect that has since self-cleared.

5. Direct drop-in replacement. Size 3 flush-mount case with the established terminal arrangement retrofits existing panel cut-outs and wiring without modification, provided the order code matches.

6. No periodic maintenance burden. Inspection and functional test at 12-month intervals is sufficient — an important consideration for remote substation fleets.

 

Typical Applications

• 11 kV, 33 kV and 132 kV substation protection panels on DEWA, ADDC, SEWA and EWEC networks
• Industrial and oil & gas switchgear in Jebel Ali, Ruwais, KIZAD and ICAD
• Generator, transformer and feeder trip circuit supervision
• Substation refurbishment, panel retrofit and like-for-like relay replacement
• Utility and contractor critical-spare inventories

 

Availability, Warranty and Support in the UAE

متوفر في المخزون — شحن سريع من دبي إلى دول مجلس التعاون الخليجي.

We hold GE MVAX31S1DE0754A and adjacent MVAX variants — MVAX11, MVAX12, MVAX21, and MVAX91 — in Dubai stock. Condition is stated explicitly on every quotation, and each relay is functionally tested before dispatch with a test record supplied.

UAE delivery is typically next working day; Saudi Arabia, Qatar, Oman, Kuwait and Bahrain within 3–5 working days. All shipments include a commercial invoice and certificate of conformity for customs clearance, backed by a 12-month replacement warranty.

 

Frequently Asked Questions

What is the difference between MVAX21 and ? MVAX21 supervises the trip circuit only with the circuit breaker closed. adds a third unit and supervises with the breaker open as well, giving preclosing supervision.

Size 3, flush mounting. MVAX12 uses a size 2 case and MVAX91 a size 8 case.

What does the D in the order code mean? Hand-reset reverse flag indication. C denotes self-reset and A denotes no flag.

Do I need an external resistor? Yes. MVAX trip circuit supervision schemes use an external resistor, typically 7400 Ω for 110/125 V service and 3100 Ω for 48/54 V. Confirm against your scheme drawing.

Can I substitute a different voltage code? No. The 0754 digits fix the DC supply type and the 110/125 V ratings of RL1, RL2 and RL3. A different code is a different relay.

Which manual applies? GE Grid Solutions publication R8010RB covers MVAX 11, 12, 21, 31 and 91.

Request a Quotation | اطلب عرض سعر

Send us the complete 15-character order code from the relay label, your nominal DC voltage and your required contact arrangement, and our team will respond with confirmed availability, interchangeability and pricing within one business day.

Technical note: Specifications are compiled from GE Grid Solutions / GE Vernova MVAX product literature and technical manual R8010RB. The MVAX range originated with GEC Measurements and passed through GEC ALSTHOM, ALSTOM T&D, AREVA T&D and Alstom Grid to GE. Manufacturers reserve the right to change specifications without notice. Verify the complete order code and scheme compatibility against your site documentation before ordering.