Function; Intended Use; Device Features; Funktional Description - Bender ISOMETER iso175 Manual

4

Function

4.1

Intended use

The ISOMETER® iso175 product line, called ISOMETER® in the following, is designed for installation in
correspondingly marked HV-components of road vehicles. There it continuously monitors the insulation
resistance of the HV system. Depending on the variant, the device communicates with a higher-level location
using different CAN protocols (standard Bender, SAEJ1939).
Other installation locations in the vehicle or in industry sectors such as e. g. the shipping, railroad or
aerospace industries are considered non-compliant with the intended use.
4.2

Device features

• Suitable for 12 V and 24 V DC systems (supply voltage)
• Insulation monitoring of DC insulation faults for unearthed systems (IT systems) DC 0...1000 V
• Continuous insulation resistance measurement R
• Response time ≤ 30 s for insulation resistances ≤ 500 /Volt and system leakage capacitances ≤ 2µF
• Insulation measurement for system leakage capacitances up to 10 µF can be configured by setting
parameters in the high capacitance ("High Capacity") profile.
• Insulation measurement also when the vehicle's HV electric system is not energised
• Intetrated self diagnosis (online self test)
• HV connection monitoring (offline self test)
• Continuous monitoring of the earth connection
• Undervoltage detection
• Earth connection can be disconnected
• Interfaces:
– Digital output for device error message (OK
• HS-CAN interface with the following protocols
- Bender CAN
- CAN-SAE J1939
– All outputs short-circuit proof
• Load-dump protection up to 58 V
4.3

Funktional description

4.3.1

Insulation resistance measurement

The overall insulation resistance measurement of an HV system is based on the patented active AMP
measuring principle. This method uses a measuring voltage source internal to the device that injects a current
into the system to be measured, and the resulting voltage drop is measured. This is carried out independently
of the voltage of the system to be monitored so that the insulation measurement can also be carried out when
the HV system is deenergised.
The measuring duration for an individual measurement generally depends on the following factors and it can
take up to 60 seconds:
• Overall insulation resistance of the HV system
• System leakage capacitance
• Measuring profile used (device parameter)
= 0...35 M (R
F_corrected
)
HS
iso175_D00415_01_M_XXEN/11.2023
ISOMETER® iso175
= 0...50 M )
F_ original
11