The insulation monitoring device HIG95+/2T produced by HAKEL for the ISOLGUARD series is designed for monitoring the insulation status of single-phase ungrounded IT power supply systems in the health sector. The insulation monitoring device enables monitoring of the ungrounded IT power supply systems according to standards IEC 60364-7-710:2002 (requirements for medical location), IEC 61557-1 and IEC 61557-8 up to the maximum operating voltage 275V AC. It is also equipped with measuring circuits which ensure evaluation and failure signalling of the monitoring system originated due to thermal (J) or current overloading of the medical transformer.
The insulation monitoring devices are equipped to display the numeric value of the measured insulation resistance. In addition, the control buttons for setting the parameters of insulation monitoring devices and signalling LED diodes can be used to display the status of the checked network.

It is possible to connect to the insulation monitoring device modules for remote signalling of the status MDS10T, MDS-D or MDS-DELTA
produced by HAKEL. Built-in alarm relay with a switching contact enables to connect devices for signalling the insulation status error and the thermal (J) or current overloading error.

Only one insulation monitoring device can be connected to the same ungrounded IT power supply system.

Basic characteristics
• The monitor for insulating statuses of AC networks with the voltage 0 to 275 V
• Measured value display of the Risol insulation resistence, thermal (J) and current overloading
• Temperature scan of the isolation transformer with one of three types of sensors
• Current overloading scan of the isolation transformer via measuring current transformer
• Signalling relay of the status of the insulating resistance with the switching contact
• Connection to the RS485 busbar, insulation strength 2500 Vrms against internal circuits and network circuits
• Option to connect the Hakel MDS-D remote monitoring panel equipped with a touch screen
• Connection for remote signalling MDS10T, MDS-D or MDS-DELTA modules produced by HAKEL.
• Option to set critical values, hysteresis values and other parameters via IMD’s buttons
• Access to setting the insulation monitoring device can be locked, the insulation monitoring device is unlocked by a combination
of buttons
• Separated supply voltage enables to also monitor a network which is not under voltage
• Module width 4M (72mm) for mounting on DIN rail 35

Dimension drawing
Dimension drawing
Installation diagram
Installation diagram
Supply voltage range Us 90 ÷ 265 V AC (47÷ 440 Hz) or 90 ÷ 370 V DC
Maximum operating voltage of the monitored ungrounded IT power supply system Un 275 V AC
Power consumption P max. 5 VA
Measuring voltage Um 12 V DC
Measuring current Im < 0,6 mA
Internal resistance of the measuring input Zi > 1 MΩ
Displayed value’s range Risol 5 kΩ ÷ 900 kΩ
Measurement accuracy 5 kΩ … 10 kΩ 2 kΩ
Measurement accuracy 10 kΩ … 900 kΩ ± 10 %
Critical insulation resistence Rcrit adjustable 50 kΩ ÷ 200 kΩ
Insulation resistance hysteresis Rhyst adjustable 0 ÷ +100 % Rcrit
Delay in response of signalling the insulation status tON adjustable 0 ÷ 60 sec, with a 1 sec step
Supply voltage range – TOF modul Un 90 ÷ 265 V AC (47÷ 440 Hz) or 90 ÷ 370 V DC
Possible type of the monitored IT power supply system single-phase AC
Power consumption TOF P maximum 4 VA
Current load measurement by measuring transformer with a transmission ratio (A): CT type By measuring transformer with a transmission ratio: 25/5 A, 30/5 A, 40/5 A, 50/5 A, 60/5 A, 80/5 A, 100/5 A
Displayed current load value’s range Iit 0,5 A ÷ 100 A (depending on the type of the measuring transformer)
Critical current load value Icrit adjustable in the range I t, with the step 1A
Current load hysteresis Ihyst adjustable 0 ÷ 20% Icrit
Measurement accuracy of the current load ± 5% (measuring transformer deviations not included)
Delay in response of signalling the current fault ItON adjustable 0 ÷ 60 sec, with a 1 sec step
Isolation transformer temperature sensor ϑsensor NC sensor or PTC thermistor or PT100 sensor
HIG95+/2T Adjustable from the device menu
Displayed isolation transformer temperature range ϑ1, ϑ2 5°C ÷ 190°C (for PT100 only)
Critical value of the isolation transformer temperature ϑcrit for PT100: adjustable 70°C ÷ 130°C, for PTC thermistor: fixed 1,6 kΩ, For NC sensor: fixed 1,6 kΩ
Hysteresis of the isolation transformer temperature ϑhyst Adjustable 0 ÷ 20 % ϑcrit (for PT100 only)
Measurement accuracy of the isolation transformer temperature ± 5% (sensor deviations not included)
Delay in response of signalling the temperature fault ϑtON Adjustable 0 ÷ 60 sec, with a 1 sec step
Signalling potential-free switching contacts / Electric strength to the internal circuits / Electric strength to the supply circuits 250 V AC / 1 A
3750 Vrms
3750 Vrms
Remote monitoring Terminals for connection of the MDS10T(+MPS) module produced by Hakel max 5 x MPS10T modules or max 2 MDS10T+MPS modules
RS485 line or MDS-D remote monitoring display module / MDS-DELTA modules from HAKEL production
Communication line: RS485 type MASTER-SLAVE, 9600 Bd, even count parity / Insulating strength to the internal circuits and to the network circuits Yes, 2500 Vrms
General data
Degree of protection according to IEC 60529 IP20
Weight m 295 g
Housing material PA - UL 94 V0
Method of assembly DIN rail 35
Recommended section of the connected conductors S 1 mm2
Operating conditions
Operating temperature ϑ -10°C ÷ +60°C
Relative humidity 28 g H2O /kg dry air
Atmospheric pressure 86 ÷ 106 kPa
Operating position any
External magnetic and electric field maximum 400 A/m
Overvoltage category / testing voltage III, according to IEC 60664-1:2007
Pollution degree 2, according to IEC 60664-1:2007
Operational mode permanent
Article number 70 930
Installation instructions (1.23 MB)
2D model (1.16 MB) for registered only
3D model (952.23 KB) for registered only
EC declaration of conformity (83.77 KB) for registered only