Strong Points


The RESYS M40 differential relay is combined with a triggered cut-off device (automatic power cut-off), to meet the following functions:
- Protect against indirect contact
- Limit earth leakage currents.
It also ensures the preventive monitoring of electrical installations with its pre-alarm function (configurable) or when used in signalling relays.


Fully configurable

- 2 relays with configurable function (alarm or pre-alarm at 50% IΔn).
- Adjustment of IΔn from 0.03 to 30 A.
- Time delay 0 to 10 s.
- Positive or negative security configurable by the user.
- Selection of toroid ratio.

Trigger accuracy by way of TRMS monitoring

Improves immunity to untimely triggers.

Real-time display of continuous leakage currents

LED bargraph shows the fluctuations of leakage currents in realtime.

Compact modular design

44 mm in width, the unit allows easy integration into dedicated enclosures. The setting buttons are protected by a sealable cover, while the available alarms are shown on the front face of the device.

Improved immunity to EMC interferences

The device has new electronics which improve electromagnetic compatibility.

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