2 Safety
Maschinenfabrik Reinhausen GmbH 2020
17
4983703/01 EN
VACUTAP
®
VV-Ex
2.5 Measures for ensuring compliance with explosion
protection requirements
2.5.1 Measures taken by the manufacturer
Maschinenfabrik Reinhausen has taken the following measures for ensuring
compliance with explosion protection requirements. You do not need to take
any special measures in this regard.
2.5.1.1 Quality of the insulating oil in the on-load tap-changer
The quality of the insulating oil required by IEC 60296 and the quality of the
synthetic esters required by IEC 61099 in the oil compartment of the on-load
tap-changer is ensured by using vacuum cells with transition resistors.
2.5.1.2 Monitoring the oil temperature in the diverter switch oil compartment
A temperature sensor is provided in the on-load tap-changer head cover for
monitoring the oil temperature in the diverter switch oil compartment. The
corresponding temperature monitoring relay is in the TAPMOTION® ED-Ex.
Temperature monitoring prevents further switching of the on-load tap-
changer when the maximum permitted temperature is reached. This maxi-
mum permitted temperature is factory-configured for each specific order for
all on-load tap-changer types (maximum 130 °C) and secured against acci-
dental incorrect adjustment.
2.5.2 Measures to be taken by the transformer manufacturer/operator
The following measures for ensuring compliance with explosion protection
requirements must be taken by the transformer manufacturer/operator.
2.5.2.1 Prescribed protective and drive components
Operate the on-load tap-changer only in conjunction with the following com-
ponents:
▪ Ex protective relay
▪ Ex motor-drive unit
▪ Ex drive shaft
