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Siemens Monitoring Relay, 3 Phase, DPDT, DIN Rail, 120V ac, 690 V ac

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£225.59

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£270.71

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RS Stock No.:
149-166
Mfr. Part No.:
3UG5618-1CR20
Brand:
Siemens
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Brand

Siemens

Product Type

Monitoring Relay

Electrical Phase

3

Contact Configuration

DPDT

Mount Type

DIN Rail

Terminal Type

Screw

Time Delay

0.1 to 30 s

IP Rating

IP20

Minimum Operating Temperature

-25°C

Supply AC Voltage

120, 690V ac

Maximum Operating Temperature

60°C

Length

90mm

Height

100mm

Width

22.5mm

Series

3UG5

Standards/Approvals

RoHS, EAC, UL, CCC, IEC 60664

Better World Claim

Concentrated or Compact Solution

Better World Product

Yes

COO (Country of Origin):
DE

Siemens 3UG5 Series Monitoring Relay, 120 to 400V Supply AC Voltage, 0.1 to 30 s Time Delay - 3UG5618-1CR20


This monitoring relay is a Compact DIN-rail device for three-phase line surveillance, providing automatic correction of rotation direction and detection of phase failure, sequence and asymmetry in industrial control systems. It monitors frequency Plus three-phase overvoltage and undervoltage windows and can operate with or without a NEUTRAL conductor, making it suitable for motor protection and network supervision across a wide AC voltage range.

Features & Benefits


• Measures three-phase voltages 90–760 V to protect equipment from supply faults
• Detects overvoltage and undervoltage across three phases for system stability
• Auto-corrects phase sequence to maintain correct motor rotation direction
• Adjustable response and OFF-delay 0.1–30 s to prevent nuisance tripping
• Two changeover contacts provide switching at up to 3A for control circuits
• Galvanic isolation between inputs and outputs to reduce interference risk

Applications


• Suitable for motor protection in conveyor and pump control panels
• Ideal for monitoring incoming supply to distribution boards
• Used for frequency-sensitive equipment protection in production lines
• Can be used for phase-sequence supervision in three-phase inverter systems

What supply voltage range can the unit monitor for control supply?


It accepts an AC control supply across a broad band from 120 to 690 V at both 50Hz and 60Hz with defined operating range factors.

How does it cope with brief mains interruptions?


The device provides a minimum buffering time of 20ms to ride through short power disturbances before signalling a fault.

What connection types and conductor sizes are supported?


Screw terminals accept solid or stranded conductors from 0.5 to 4 mm² with a stripped length of 10 mm and a recommended tightening torque of 0.6–0.8 N·m.

What mechanical and electrical endurance can be expected from the switching elements?


Typical mechanical life is around 10,000,000 cycles and electrical endurance at AC-15/230 V is about 100,000 operations.

What environmental limits apply during normal operation?


It is rated for operation from −25°C to +60°C, with a maximum installation altitude of 2000m and relative humidity up to 70%.

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