3 Product description
Maschinenfabrik Reinhausen GmbH 2020
21
5993419/02 EN
VACUTAP
®
VMS
®
11 Connection terminal
12 Pressure equalization element
13 Cylinder head screw for protective
conductor connection
The protective relays RS 2003 and RS 2004 have a 1/2"-14NPT adapter in
place of the cable gland.
3.1.4.1.3 Nameplate
The nameplate is on the back of the protective relay.
Figure 9: Nameplate
3.1.4.2 Pressure monitoring device DW
3.1.4.2.1 Function description
The DW 2000 pressure monitoring device protects the on-load tap-changer
from impermissible pressure increases, contributing to the safety of the
transformer. The pressure monitoring device is installed on the outside of the
on-load tap-changer and is tripped by impermissible static and dynamic
pressures in the on-load tap-changer oil compartment.
The pressure monitoring device uses a concept where a corrugated tube
acts as a barometer together with a spring providing counter force. This as-
sembly is mechanically linked to the sensor on the snap-action switch.
The pressure increase activates the sensor on the snap-action switch, which
flips into the OFF position. This triggers the circuit breaker and de-energizes
the transformer. The sensor on the snap-action switch has to be reset to the
initial position by hand after tripping.
Low-energy interference does not cause the pressure monitoring device to
trip since the required tripping pressure is not reached. The tripping pressure
is set at the factory and prevented from being changed.
