Phase monitor
RL 9877

The measuring relays RN 9877 and RL 9877 of the VARIMETER series monitor overvoltage, undervoltage, voltage range, phase asymmetry and phase sequence in 3-phase or single-phase systems. The measurement is very simple and without extensive wiring as there is no auxiliary power supply necessary. The monitoring functions are easily selectable using a single turn switch without complex menu structure. The early detection of up-coming break downs and preventive maintenance avoid expensive damages. As user you profit from the reliability and availability of your plant.

Advantages
. Preventive maintenance
. For better productivity
. Always right directions of motors and pumps
. Safe monitoring of motors and plants with phase failure detection
. High repeat accuracy
. Wide measuring voltage range
. Selectable monitoring function
. Easy setting

Features
. According to IEC/EN 60255-1
. For monitoring of AC 3- and single-phase with 50 /60 Hz
. Detection of
- Overvoltage
- Undervoltage
- Voltage range excess
- Phase failure
- Phase asymmetry
- Missing neutral e.g. broken neutral wire
- And phase sequence in 3-phase systems
. With or without neutral
. Without separately auxiliary voltage (internal supply from all 3 phases)
. Output: 1 changeover contact
. De-energized on trip
. Adjustable hysteresis for reset
. Adjustable switching delay
. Fast fault detection
. Width:
- RL 9877: 35 mm
- RN 9877: 52.5 mm

Technical specifications
Width: 35mm
Approvals: UL
Enclosure design: Distribution board
1- / 3-phase: 3, 1
Standard measuring range: 3/N AC 80 - 230 V / 45 - 130 V
Measuring range max.: 230 V
Output contacts: 1 C/O contact
Auxiliary voltage: Without
Type: RL 9877


Manufacturer: E. Dold & Söhne GmbH & Co. KG
Type: RL9877.11/61 3/N AC80-230/45-130V
Art. No.: 0066426