The insulation monitoring device HIG95-DELTA 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 MDS-DELTA or MDS-D 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 MDS-DELTA or MDS-D 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 2M for mounting on DIN rail 35
Dimension drawing
Dimension drawing
Installation diagram
Installation diagram
Supply voltage range Us 85 ÷ 264 V AC (47÷ 63) Hz
Possible type of the monitored IT power supply system AC
Maximum operating voltage of the monitored ungrounded IT power supply system Un US=UN
Power consumption P max. 4 VA
Measuring voltage Um 12 V DC
Measuring current Im < 0,6 mA
Internal impedance of the measuring input Zi > 1 MΩ
Internal direct resistance Ri > 32 kΩ
HIG95-DELTA tan < 5 sec
Permissible system leakage capacitance Ce 10 uF
Measuring range RF 5 kΩ ÷ 10 MΩ
Measurement accuracy 5 kΩ … 10 kΩ 2 kΩ
Measurement accuracy 10 kΩ … 900 kΩ ± 10 %
HIG95-DELTA ± 15 %
Reaction value’s setting range Ran Ran adjustable 50 kΩ ÷ 500 kΩ
Insulation resistance hysteresis Rhyst adjustable 0 ÷ +100 % RAN
Delay in response of signalling the insulation status tON adjustable 0 ÷ 60 sec, s krokem 1 sec
Current load measurement by measuring transformer with a transmission ratio (A): CT type By measuring transformer with a transmission ratio 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 according to measuring current transformer type with 1 A step, see Icritvalue range for measuring transformers table
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 1 to 2 NC sensors or 1 to 2 PTC thermistors or 1 to 2 PT100 sensors
HIG95-DELTA Adjustable from the device menu
Displayed isolation transformer temperature range ϑ1, ϑ2 5 ÷ 220°C (for PT100 only)
Critical value of the isolation transformer temperature ϑcrit for PT100 adjustable in the range 50 ÷ 130 °C
for PTC thermistor 1,6 kΩ is the decision level
For NC sensor 1,6 kΩ is the decision level
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 1 sec step
Two signalling switching contacts with optional position NO or NC / Electrical strength to the internal circuits and supply circuits 24 V∼ / 1 A / 3000 ∼
30 V⎓ / 1 A / 3000 ∼
Remote monitoring ISOLGUARD RS485 communication line with a possible connection of remote monitoring modules MDS-D and MDS-DELTA produced by HAKEL
Communication line: RS485 type MASTER-SLAVE, 9600 Bd, even count parity / Insulating strength to the internal circuits and to the network circuits Yes 2500 V∼
Degree of protection according to IEC 60529 front panel IP40 covers except front panel IP20
Weight m 154 g
HIG95-DELTA IEC 61326-2-4
Housing material PA - UL 94 V0
Method of assembly DIN rail 35
Recommended section of the connected conductors S 1 mm2
Operating temperature ϑ Operating temperature -15 °C ÷ +60 °C, Shipping temperature -25 °C ÷ +70 °C
Operating position any
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 70 940
EC declaration of conformity (83.77 KB) for registered only