BENDER IRDH575 Insulation Monitoring

The measurement circuit measures voltage ≤ 40 V, current ≤ 220 μ A, and internal DC resistance ≥ 180 k Ω. It is allowed for external DC voltage B1 ≤ 810 V and B2 ≤ 1060 V. System leakage capacitance ≤ 150 (500) μ F. The response value is 1 k Ω... 10 M Ω, and the relative error is 0%...+20% within the range of 10 k Ω... 10 M Ω. The range of 1 k Ω... 10 k Ω is+2 k Ω. The lag is 25%+2 k Ω.

Display as backlit LCD, 4 × 16 characters, character height 5 mm. Analog output 0/4... 20 mA, load ≤ 500 Ω. The maximum cable length of RS-485/BMS is 1200 meters, and it is recommended to use shielded cable J-Y (ST) Y 2 × 0.6. The switch components consist of three sets of SPDT contacts: K1 alarm 1, K2 alarm 2, K3 equipment fault/EDS alarm. K1 and K2 can be selected as normally excited or de excited, and are factory de excited; K3 is normally excited. Contact rated AC 250 V/DC 300 V, connect 5 A, disconnect 2 A (AC 230 V, cos φ=0.4... 0.2 A; DC 220 V, L/R=0.04 s). The electrical lifespan is 12000 cycles.

In terms of selection: IRDH575B1-427 is AC/DC 20... 575 V, powered by DC 19.2... 72 V; IRDH575B1-435 is 3 (N) AC/DC 20... 575 V, powered by AC 88... 264 V/DC 77... 286 V; IRDH575B1-4227 is 3 (N) AC/DC 20... 150 V, powered by DC 19.2... 72 V; IRDH575B1-4235 is AC/DC 20... 150 V, powered by AC 88... 264 V/DC 77... 286 V; IRDH575B2-435 is 3 (N) AC 340... 760 V, DC 340... 575 V, powered by AC 88... 264 V/DC 77... 286 V. Some models measure a voltage of 10 V. When selecting, attention should be paid to the system voltage, power supply method, and measurement voltage requirements.

Debugging and common troubleshooting

When debugging IRDH575, the system voltage, power supply voltage, fuses, grounding connections, and RS-485 terminals should be confirmed first. Set response value, alarm mode, locked/unlocked, analog output type, and EDS mode. If EDS positioning is used, the EDS address, channel, and test current need to be set, and the direction and wiring of the current transformer need to be confirmed.

Common problem one: Frequent insulation alarm. Check whether the actual insulation resistance and response value are too small, whether the system leakage capacitance is too large, whether the frequency converter filter capacitance is affected, and whether the wiring terminals are damp. The INFO menu allows you to view the leakage capacitance and adjust the response value or troubleshoot the load in batches if necessary.

Common problem 2: System malfunction alarm. Focus on checking the grounding of KE equipment, L1/L2/L3 wiring, power supply insurance, and self-monitoring circuit. If the device is poorly grounded, IRDH575 may report a system malfunction.

Common problem three: EDS is not located. Confirm whether the EDS LED is activated, whether the AUTO mode is turned on, whether the EDS address and channel are correct, whether the test current is sufficient, and whether the transformer is installed in the correct branch. If the pulse signal is weak, the test current can be increased, but it must be ensured that it does not exceed the allowable value of the system.

Common problem four: RS-485 communication abnormality. Check the polarity of A/B, whether the terminal resistance S1 is set to ON at the end of the bus, whether the shielding layer is single ended grounded, and whether the cable length exceeds 1200 m. Ethernet, MODBUS, or PROFIBUS can be connected through a protocol converter.

Common problem five: Analog output deviation. Confirm the 0... 20 mA or 4... 20 mA settings, whether the load is ≤ 500 Ω, and whether the PLC analog input configuration matches.

Application suggestions

IRDH575 is suitable for floating ground systems that require continuous power supply and high reliability. For multi branch systems, it is recommended to adopt the architecture of IRDH575+EDS460/EDS461+W series current transformers. The communication main circuit can use EDS460, and the PLC or DC control circuit can use EDS461. Each isolation system is independently configured with an IRDH575 to avoid cross system interference. For coupled ungrounded systems, STANDBY contacts can be used to achieve coordinated operation of multiple A-ISOMETERs.

In scenarios such as ships, mines, metallurgy, chemicals, data centers, energy storage, and rail transit, the early warning and positioning capabilities of IRDH575 can significantly shorten troubleshooting time and reduce unplanned downtime. Its RS-485, analog output, and relay interfaces make it easy to connect to existing SCADA, PLC, or BMS systems.