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Siemens Monitoring Relay, 3 Phase, SPDT, DIN Rail, 5mA to 5A, 200V ac, 690 V ac

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£127.43

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RS Stock No.:
149-148
Mfr. Part No.:
3UG5512-1AR20
Brand:
Siemens
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Brand

Siemens

Product Type

Monitoring Relay

Electrical Phase

3

Contact Configuration

SPDT

Mount Type

DIN Rail

Minimum Current Sensed

5mA

Power Consumption

1.8W

Maximum Current Sensed

5A

Terminal Type

Screw

IP Rating

IP20

Time Delay

20 ms

Relay Contact Current

3A

Minimum Operating Temperature

-25°C

Supply AC Voltage

200, 690V ac

Maximum Operating Temperature

60°C

Standards/Approvals

IEC 60947-1 2, CE, RoHS, EAC, CCC

Width

22.5mm

Series

3UG5

Length

90mm

Height

100mm

Better World Claim

Concentrated or Compact Solution

Better World Product

Yes

COO (Country of Origin):
DE

Siemens 3UG5 Series Monitoring Relay, 3 Phase Electrical Phase, 200/690V Supply AC Voltage - 3UG5512-1AR20


This monitoring relay provides continuous supervision of three‑phase supplies, detecting phase sequence, phase loss and asymmetry for industrial control systems. It monitors AC voltages across a wide band and reacts via a single changeover contact to protect downstream equipment and signal control circuits in automation and electrical installations.

Features & Benefits


• Monitors 3‑phase voltages and detects wrong sequence, preventing equipment damage
• Senses asymmetry indirectly using preset voltage limits to maintain motor health
• Wide AC monitoring range supports 160–760 V for versatile installation
• Fast buffering keeps operation for at least 20ms during brief supply interruptions
• Relay contact rated for 3A at AC‑15 to Interface with control loads
• Low power draw at 1.8W reduces panel heat and energy use

**Applications**


• Suitable for motor starter protection against phase loss in factories
• Ideal for control panels requiring phase sequence verification before start‑up
• Used with distribution systems to alarm on unbalanced supply conditions
• Can be used for automated machinery that must prevent operation under asymmetry

What type of output switching does it provide?


It uses one changeover (SPDT) auxiliary contact with silver‑tin‑oxide contact material for switching control circuits.

How should conductors be terminated?


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

What environmental limits apply during operation?


Rated ambient temperature range during operation is −25 to 60 °C with maximum relative humidity of 70% and installation altitude up to 2000m.

How resilient is it to electrical and mechanical stress?


It meets surge and EMC immunity levels including 6kV surge resistance and withstands sinusoidal shock at 15 g/11ms and vibration per IEC standards.

Are there removable connection options for maintenance?


Removable Terminal blocks are provided for both the main and auxiliary/control circuits to simplify replacement and wiring tasks.

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