Engaging/Disengaging the ERMS Function

@experts: this topic is shared between MTZ1 with MicAct User Guide and MTZ2/MTZ3 with MicAct User Guide

Presentation

The ERMS function is used to reduce protection settings so that the circuit breaker trips as soon as possible when an electrical fault occurs. Minimizing the time between the electrical fault and circuit breaker trip helps to reduce the risk of injury when qualified electrical personnel are near energized equipment.

When the ERMS function is engaged, the ERMS protection settings replace the standard protection settings.

Availability

The ERMS function is available on MicroLogic Active 2.0, 5.0 and 6.0 control units for IEC standard.

Operating Principle

The ERMS function can be engaged or disengaged by using the ERMS button, or by using an external selector switch connected to the BCIM module.

While the ERMS function is engaged:

The ERMS LED (A) is lit in blue.
The LSIG home screen (B) is blue.
The Quick View screens are blue.
All other screens are not blue.

For more information about the ERMS function, and how to engage and disengage the ERMS function, refer to DOCA0265•• MasterPacT MTZ - MicroLogic Active Control Unit - User Guide in Related Documents at the beginning of this guide.

Engaging the ERMS Function

DANGER
hazard of incorrect ERMS status Do not rely on the ERMS status signaled on the BCIM IO port. Use the blue ERMS LED on the MicroLogic Active control unit to check ERMS status before working on or inside the equipment. Failure to follow these instructions will result in death or serious injury.

The ERMS can be engaged in different ways, according to the circuit breaker configuration and its accessories:

Type	Accessories	Action
Through the ERMS button on MicroLogic Active control unit	–	Press the ERMS button to engage the ERMS function.
Through an external selector switch connected to the BCIM module	BCIM module External selector switch wired by customer	Turn the external selector switch to the Engaged position. The BCIM module must be configured in ERMS mode.

Disengaging the ERMS Function

DANGER
HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH Prior to disengaging ERMS: Carefully inspect your work area, and remove any tools and objects left inside the equipment. Ensure that all personnel are away from the equipment, and devices, doors, and covers are in place. Failure to follow these instructions will result in death or serious injury.

The way to disengage the ERMS function depends on how it was engaged:

Type	Accessories	Action
Through the ERMS button on MicroLogic Active control unit	–	Press the ERMS button to disengage the ERMS function.
Through an external selector switch connected to the BCIM module	BCIM module External selector switch wired by customer	Turn the external selector switch to the Disengaged position.