Voltage monitor ONLINE USV-Systeme ONLSW230 — 230V 50Hz mains voltage monitoring device

The ONLINE USV-Systeme ONLSW230 — 230V 50Hz mains voltage monitoring device continuously monitors the quality of single-phase mains supply at 230 V and 50 Hz. It detects under-voltage, over-voltage and power interruptions and provides a stable signal for alarm systems or uninterruptible power supplies (UPS). The device is intended for installation where stable mains voltage is required to protect sensitive electronics, industrial controllers and critical infrastructure from supply anomalies and unexpected outages.

Advantages

The voltage monitor offers continuous detection of voltage deviations and interruptions, enabling timely responses from connected protective equipment. Its compact design allows for easy integration into existing electrical installations and UPS setups without occupying significant space. The unit delivers reliable signal outputs that can be used to trigger alarms, initiate UPS transfer or shut down connected loads to prevent equipment damage.

Suitable for

• Integration with UPS systems to coordinate transfer to battery power
• Protection of servers, network hardware and telecommunications equipment
• Monitoring of industrial control panels and PLC-driven machinery
• Use in medical and laboratory equipment environments where supply integrity matters
• Facility management systems for automated alerting of power anomalies

Key specifications

• Nominal input voltage: 230 V AC
• Nominal frequency: 50 Hz
• Monitored conditions: under-voltage, over-voltage and power interruption detection
• Signal outputs: relay/contact outputs for alarm and control functions
• Mounting: panel or DIN-rail compatible form factor for electrical cabinets
• Operating environment: intended for indoor electrical installations

How to use

Install the unit in the electrical distribution cabinet close to the supply feed and connect the input to the 230 V AC supply according to the wiring instructions. Connect the relay or contact outputs to the UPS control input, alarm system or to a device that will execute protective actions such as load disconnect or orderly shutdown. Configure the connected systems to respond to the monitor’s signal thresholds so that transfer to backup power or alerts occur at the desired voltage limits. Verify wiring and test operation under controlled conditions before placing the system into regular service.

Usage recommendations

Place the device in a dry, ventilated enclosure and ensure connections are tightened per local electrical codes. Periodically test the monitor and connected protective equipment to confirm correct detection and response to under-voltage, over-voltage and interruptions. Coordinate threshold settings and response logic with your UPS or control system to avoid unnecessary transfers or shutdowns while ensuring timely protection.