The insulation monitoring device HIG95+ 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 system according to standards IEC 60364-7-710:2002 (requirements for medical location), IEC 61557-1:2007 and IEC 61557-8:2007 up to the maximum operating voltage 275V AC. Device also allows the evaluation of thermal and current load of the isolation transformer.
The insulation monitoring device enables to display the numeric value of the measured insulation resistance and also current and thermal load of the isolation transformer, than there are buttons for setting module parameters and signalling LED diodes for displaying the status of monitored power supply system and of the device. To the insulation monitoring device it is possible to connect remote monitoring modules of the monitored power supply system status from the MDS line produced by HAKEL.
It is possible to connect MDS-D module with touch screen display via RS485 bus, which serves to display current measured values and current device setup. Communication via the RS485 uses protocol based on the PFOFIBUS protocol.
Built-in signalling relay with a switching contact enables remote monitoring of the insulation status fault and eventually also the thermal (ϑ) or current overload.

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

Basic characteristics
Insulation monitoring device for AC systems with 0 to 275 V voltage
Display of the measured insulation resistance, current load and thermal load
Isolation transformer temperature measurement by using one of 3 sensor types
Isolation transformer current load measurement by the measuring current transformer
Signalling contacts for IT system faults
Connection to RS485 bus, insulation strength 2500 Vrms against the internal circuits and network circuits
Optional connection of the touch screen panel of HAKEL MDS-D remote monitoring system
Optional connection of HAKEL MDS10T remote monitoring system
Optional connection of HAKEL MDS-DELTA remote monitoring system
Optional communication with a master system via RS485 bus
Communication protocol description available on request
Pushbuttons available for setting the critical values, hysteresis values and other parameters
Access to the IMD parameter setting with the pushbuttons can be locked/unlocked by a button combination
Separate supply voltage also allows to monitor IT power supply systems, which are not under voltage

Dimension drawing
Dimension drawing
Installation diagram
Installation diagram Počet fotek v galerii: 5
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 maximum 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
Temperature sensor type selection, both sensors of the same type 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 H2 O /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 70 929

1P signalling relay with one switching contact

           MDS10T remote monitoring module of the insulation monitoring device

           MDS-D remote monitoring module including a display

           MDS-DELTA remote monitoring module with communication via the RS485 bus

Installation instructions (1.38 MB)
2D model (1.16 MB) for registered only
3D model (952.23 KB) for registered only
Drawings in DWG format (241.94 KB) for registered only
EC declaration of conformity (83.77 KB) for registered only