GYDCG-UBCS1 DIN Rail DC Insulation Monitor for 100~1000VDC Systems

Description

The GYDCG-UBCS1 DIN rail DC insulation monitor continuously monitors the insulation resistance between the positive and negative poles and ground in 100–1000VDC floating DC systems. It measures 0KΩ–10MΩ, supports RS485 communication with MODBUS RTU protocol, and has an internal self-test function. It is used in EV DC charging systems, photovoltaic systems, energy storage systems and DC power grids.

Product description

GYDCG-UBCS1 DC Insulation Monitor features an insulation monitoring start/stop function. Once activated, it continuously monitors the positive and negative poles-to-ground insulation resistance. Monitoring results are unaffected by DC voltage fluctuations or the symmetry of positive and negative insulation resistance.

• Monitors positive and negative poles-to-ground insulation resistance in 100–1000VDC floating DC systems.
• Resistance measurement range: 0KΩ–10MΩ.
• DC voltage monitoring range: 0–1000VDC.
• Supports RS485 communication with MODBUS RTU protocol.
• Features a DC reverse-polarity alarm function.
• Supports two operating modes: Automatic Bridge Switching Mode (unbalanced bridge method) for monitoring insulation resistance to ground, and Fixed Bridge Mode (balanced bridge method) for monitoring voltage to ground.
• Features an internal self-test function for the insulation monitoring module.
• Suitable for EV DC charging systems, photovoltaic systems, energy storage systems, DC power grids, and other DC systems.

Additional Performance Highlights

• Dual-voltage compatibility: Supports both 12V and 24V power-supply inputs.
• Reliable real-time monitoring: Insulation monitoring remains stable under low-frequency DC-voltage fluctuations.
• Fast setup and response: Uses adaptive ground-capacitance matching for faster measurements, with communication parameters configurable via onboard DIP switches.

What are the two bridge modes for?

In Automatic Bridge Switching Mode (unbalanced bridge method) the module measures the insulation resistance of the positive and negative poles to ground. In Fixed Bridge Mode (balanced bridge method) it monitors voltage to ground instead. Which mode you use depends on whether your controller needs resistance values or voltage-to-ground values from the floating DC system.

Which UBCS1 version fits my system?

• 100~1000VDC systems: this GYDCG-UBCS1.
• 50~250VDC systems: GYDCG-UBCS1-250 250V DC insulation monitor.
• 10~60VDC systems: GYDCG-UBCS1-60 60V DC insulation monitor.
• If you want relay, indicator and buzzer outputs in a compact unit, see the GYDCG-UB1K compact insulation monitor.

Frequently asked questions

What DC voltage range does the GYDCG-UBCS1 monitor?

Insulation monitoring in 100–1000VDC floating DC systems, with DC voltage detection from 0 to 1000VDC.

Which communication protocol does it use?

RS485 communication with MODBUS RTU protocol.

Does it include a reverse-polarity alarm and self-test?

Yes. It has a DC reverse-polarity alarm and an internal self-test function for the insulation monitoring module.

How do I set the communication parameters?

With the onboard DIP switches.

Related guide

• How does an insulation monitoring device work?

Technical support and certificates

Gongyuan (Suzhou Gongyuan Automation Technology Co., Ltd.) has focused on insulation monitoring since 2017 and operates a quality management system built to the ISO 9001:2015 standard. Send your DC voltage, communication protocol and application through our contact page for a model recommendation. Certificates and test reports are listed on the Certifications page. Specifications on this page come from Gongyuan’s product documentation; please confirm the final model and options with our engineers before ordering.