Insulation monitors

Unscheduled downtimes of machines and plants mean a considerable cost factor. By early detection of insulation faults DOLD insulation monitors help to prevent failures of electrical equipment and thus ensure a better operating reliability and plant safety.

They are used both in earthed and also non-earthed systems, but differ in their function principle:

In earthed systems (TN systems) DOLD differential-current monitors detect fault current with the principle of differential-current measurement and are mainly used to avoid cost-intensive downtimes and to prevent the risk of fire which is latent in the case of slowly evolving insulation faults.

In non-earthed systems (IT systems), the insulation resistance to earth of the system to be monitored is measured. Such systems are secured by insulation monitors the use of them in IT systems is required by law by the norm “Safety of Machinery” DIN EN 60204-1 or DIN VDE 0100-410. Thanks to deliberately kept simple functionality of DOLD’s insulation monitors customers benefit from a considerable cost advantage combined with the high quality standard accustomed from DOLD.

• Save space thanks to compact design
• Cost-effective and easy-to-use by kept simple functionality
• Flexible by extended application range of our insulation monitors for systems up to 500V AC and 1000 Hz, i.e. also application for 400V three-phase systems Monitor DC systems up to 280V without auxiliary voltage
• Improve efficiency: avoid unscheduled downtimes and data lossesImprove operational reliability and safety: monitor also at standstill, no interruption of operation in the case of single-phase-to-earth fault
• Better fire safety: detect slowly evolving insulation faults, minimize accidental arcs as frequent fire cause, split and separetely monitor systems in fire- and exlosion-prone areas
• Improve workplace safety: no malfunctions of machinery and systems due to earth faults
• Save time during maintenance and repair: reduce cost by early detection of insulation faults and well-aimed repair

Insulation monitors: for non-earthed systems
FunctionSystem
type
Max.
voltage
[V]
Threshold
(RAN)
up to [kOhm]
with aux.
voltage
Earth fault
indicator
Connection
for indicator
Test
key
clear
key
Housing Style:
Width [mm]
Type
Insulation monitorAC;
three-phase
500Adjustable,
up to 100
++++Distribution board: 35; 70
Switch cabinet: 35; 70
IL 5880, IP 5880,
SL 5880, SP 5880
Insulation monitorAC;
three-phase
500Adjustable,
up to 100
++++Switch cabinet: 22,5MK 5880N
Insulation monitor
for medical areas
AC;
three-phase
500Adjustable,
up to 500
++++Distribution board:
52,5; 70
IN 5880/710,
IN 5880/711,
IP 5880/711
IT Line monitor for medical
areas monitors insulation,
current and temperature
AC;
three-phase
500Fixed, 50+++Distribution board:
105; 140
IR 9112/710,
IS 9112/711,
IS 9112/712
Insulation monitoring relay
motor windings
AC;
three-phase
400Adjustable,
up to 2000
++Switch cabinet: 45BD5877/241
Insulation monitoring relay
with voltage monitoring
for motor windings
AC;
three-phase
400Adjustable,
up to 2000
Switch cabinet: 100BO 5877/011
Insulation monitorDC500Adjustable,
up to 200
+++Distribution board: 35
Switch cabinet: 35
IL 5881,
SL 5881
Insulation monitorMixed
systems
500Fixed, 440+++++Switch cabinet: 100AN 5890
Insulation monitorMixed
systems
1000Fixed, 440++++Switch cabinet: 100AN 5873
Insulation monitorAC;
three-phase
500Adjustable,
up to 2000
+++++Distribution board: 140RP 5888
Following product are also available:
AG 5876, AI 895, AI 897, AI 898, AN 5872, EH 5878