K-ELECTRIC 103059 Undervoltage Monitoring Relay, 24-240 V AC/DC, 1 Changeover, DIN Rail

Voltage dips and brownouts can cause equipment malfunction, data loss, and premature wear in industrial and commercial installations. The K-ELECTRIC 103059 undervoltage monitoring relay continuously supervises single-phase AC/DC networks and disconnects the load when voltage falls below a safe threshold, protecting motors, controllers, and sensitive electronics from undervoltage damage.

Who is it for

Electrical engineers, panel builders, and maintenance technicians who need reliable undervoltage protection for automation systems, HVAC equipment, pumps, and lighting circuits. It is ideal for DIN rail distribution boards and control cabinets in industrial environments.

Main features

• Wide nominal voltage range: 24–240 V AC/DC, suitable for various supply systems.
• Adjustable undervoltage threshold from 75% to 95% of nominal voltage.
• Fixed hysteresis of 5% to prevent relay chatter near the threshold.
• Adjustable delay time from 0.1 to 10 seconds to ignore brief voltage dips.
• 1 changeover contact (SPDT) rated 250 V AC / 5 A for control or alarm circuits.
• Three LED indicators for power, undervoltage condition, and relay status.
• Compact 1 TE (17.5 mm) DIN rail housing saves panel space.
• Screw terminals for secure wiring; IP40 housing and IP20 terminals.

Specifications

• Function: Undervoltage monitoring
• Supply voltage: 24–240 V AC/DC
• Output: 1 changeover contact (SPDT)
• Contact rating: 250 V AC / 5 A
• Undervoltage threshold: 75–95% adjustable
• Hysteresis: 5%
• Delay time: 0.1–10 s adjustable
• LED indicators: Power, Undervoltage, Relay ON
• Mounting: DIN rail (35 mm)
• Connection: Screw terminals
• Operating temperature: -20°C to +55°C
• Protection class: IP40 (housing), IP20 (terminals)
• Module width: 1 TE (17.5 mm)

Tips

Set the undervoltage threshold according to the minimum voltage your equipment can tolerate. Use the adjustable delay to avoid nuisance tripping during motor starting or short-term voltage fluctuations. The relay's changeover contact can be wired for either fail-safe or alarm indication, depending on your control logic.