Eaton/Moeller
Electronic Measuring Relay
Overview

EMR4-F
The compact EMR4-F phase sequence relay can be used for monitoring the clockwise rotation of movable motors where the phase sequence is important, as related to pumps, saws, and drilling. It provides protection against damage by means of phase sequence and phase failure monitoring.

EMR4-W
The EMR4-W phase Measuring Relay is optimal for monitoring the phase sequence and the applied voltage level, subsequently offering protection against destruction or damage to individual system sections.

• A dial allows setting of the required voltage for both the minimum undervoltage and maximum overvoltage within a defined window.
• Both on-delayed and off-delayed functions are available. The on-delayed setting enables short overvoltages or voltage dips to be bridged. The off-delay setting allows faults to be stored for the time set.
• The delay time can be set between 0.1s and 10s. The relay picks up if the phase sequence and voltage are correct. After it has dropped out the device does not pick up again until the voltage goes over a 5% hysteresis.

EMR4-A
The EMR4-A phase imbalance Measuring Relay module is the ideal protective device for phase loss protection. The detection of phase loss on the basis of phase shift means that reliable phase loss detection is ensured, even with large amounts of energy regenerated to the motor (up to 95% voltage feedback).

EMR4-R
EMR4-R insulation Moeller Measuring Relays increase operation safety and reliability. IEC/EN 60 204 "Safety of Machinery" stipulates that auxiliary circuits must be protected with earth leakage monitors in order to increase operating safety. This Measuring Relay is primarily used for this purpose, as well in areas for medical applications with similar requirements.

• A changeover contact indicates an earth fault and therefore allows faults to be rectified without the need for expensive downtimes.
• The devices can be provided with an optional fault memory that requires a fault to be acknowledged after it has been rectified.
• A test button is provided to test the functioning of the device at any time.

EMR4-I
The EMR4-I current monitors are suitable for both AC and DC monitoring tasks. The selectable lower or upper tripping limit means that they can be used for the underload or overload monitoring of pumps and drilling machines.

• They are available in two versions, each with three measuring ranges (30/100/1000 mA, 1.5/5/15 A).
• The multi-voltage coil allows these relays to be used for a wide range of applications.

EMR4-N
The EMR4-N level Moeller Measuring Relays are used primarily to protect pumps from running dry or for the control of liquid levels. They operate by means of sensor monitoring the maximum level and one sensor monitoring the minimum. A third sensor is used for the chassis potential.

EMR4-N500
The EMR4-N500 level Measuring Relay has an enhanced sensitivity and is therefore also good for less conductive media, such as foams. An integrated on and off-delay function between 0.1s and 10s ensures that even moving liquids can be monitored reliably.