Schneider Electric RM22UA32MR monitoring for over- and under-voltage with memory 2W content_copy

The voltage monitoring relay RM22UA32MR from Schneider Electric belongs to the Harmony control relays series and is designed for continuous monitoring of a measurement circuit for over- or undervoltage exceeding a set voltage threshold in the range of 1 to 100 V AC/DC. The device operates as a voltage monitor and allows selection between detecting overvoltage, undervoltage, or both in the so-called window mode. Monitoring occurs with a measurement cycle of up to 100 ms, with the value captured as a true RMS value. The settings for the threshold, switching hysteresis, and time delay are manually adjustable via controls on the front panel. The hysteresis is fixed at 3 % of full scale in window mode, while an adjustable hysteresis of 5 to 50 % of the threshold setting is also possible. The time delay is adjustable from 0.1 to 30 seconds, with an accuracy of ±10 % of the scale value. The reset time is 1500 ms at maximum voltage, and the turn-on delay is 600 ms.

Applications include monitoring voltage supplies in industrial plants, machine controls, or in systems where stable voltage is critical for operation. The device is designed for use in single-phase systems and monitors the voltage in the measurement circuit independently of the supply voltage. Power supply is via a wide-range power supply in the range of 24 to 240 V AC/DC, enabling universal adaptation to various supply voltages. Power consumption is 3.5 VA in AC operation and 1.5 W in DC operation. Measurement accuracy is less than 1 % across the entire range, with a temperature drift of 0.05 % per degree Celsius taken into account.

Functions and equipment in detail include two relay changeover contacts, each rated up to 8 A. Switching capacity is 2000 VA, with a maximum switching voltage of 250 V AC. The contacts are cadmium-free and have an electrical life of 100,000 cycles and a mechanical life of 10,000,000 cycles. The output contacts are connected via screw terminals, which are designed for conductors from 0.2 to 3.3 mm² (AWG 24 to AWG 12), both solid and stranded. The terminals must be tightened with a torque of 0.6 to 1 Nm.

Technology explained simply shows that the device continuously monitors the voltage in the measurement circuit and switches the output relays when the set threshold is exceeded or undershot. Settings are adjusted via potentiometers on the front, which can be protected by a transparent cover to prevent unintended changes. An illuminated scale pointer enables visual control of the setting even from a distance. A front-mounted diagnostic switch allows temporary deactivation of the output relays to test the entire system. Closing the transparent cover automatically resets this switch. Two LEDs indicate operating and fault status.

Compatibility and accessories include use with PLC controls such as the TM221CE16T, which communicates via Ethernet and is designed for positive logic. The device is designed for industrial environments and complies with standards IEC 60255-1 and certifications GL, UL, CCC, EAC, CE, RCM, and CSA. Protection rating is IP20 at terminals, IP20 at the housing, and IP20 at the front plate, providing limited protection against touch and dust. Insulation is between supply and measurement circuit, with overvoltage category III. Operating temperature ranges from -20 to 50 °C at 60 Hz or -20 to 60 °C at 50 Hz, with storage temperature from -40 to 70 °C. Relative humidity is 93 to 97 % at 25 to 55 °C. Vibration resistance is 0.075 mm (10–58.1 Hz) and 0.035 mm (58.1–150 Hz) in operation, with shock resistance of 15 Gn (not in operation) and 5 gn (in operation). The housing is made of polycarbonate and is designed for mounting on a 35 mm DIN rail. Width is 22.5 mm, height is 90 mm.

Mounting and installation are performed on a standard 35 mm DIN rail, with screw terminals provided for wire connections. Settings are adjusted on-site, with the transparent cover protecting the controls against unintended changes. The terminals are designed for various conductor cross-sections, and tightening torques must comply with IEC 60947-1.

Operational advantages include universal voltage supply, simple adjustment of thresholds and hysteresis, high measurement accuracy, and long contact life. The integrated diagnostic function and visual LED indicators simplify maintenance and fault diagnosis. The combination of wide-range power supply and robust design makes the device suitable for a wide range of industrial applications.

Complementary
[Us] rated supply voltage	24...240 V AC/DC 50/60 Hz, non self-powered
Supply voltage limits	20.4…264 V AC/DC
Power consumption in VA	3.5 VA AC
Measurement range	1...100 V AC/DC
Maximum measuring cycle	100 ms measurement cycle as true rms value
Hysteresis	3 % fixed of full scale for window mode; 5…50 % adjustable of threshold setting
Repeat accuracy	+/- 0.5 % for input and measurement circuit; +/- 2 % for time delay
Measurement error	< 1 % over the whole range with voltage variation; 0.05 %/°C with temperature variation
Time delay type	Adjustable 0.1...30 s, +/- 10 % of the full scale value Tt- time delay upon fault
Setting accuracy of time delay	10 %
Reset time	1500 ms at maximum voltage
Power on delay	600 ms
Output contacts	2 C/O
nominal output current	8 A
Maximum switching voltage	250 V AC
Switching capacity in VA	2000 VA
Minimum switching current	10 mA at 5 V DC
Maximum switching current	8 A AC
Electrical durability	100000 cycles
Mechanical durability	10000000 cycles
Contacts material	Cadmium free
Maximum power consumption in W	1.5 W DC
Resistance across terminals	110 kOhm at E2-M terminals; 22 kOhm at E1-M terminals; 220 kOhm at E3-M terminals
Insulation	Between supply and measurement
Contractual warranty
Warranty (in months)	18
Environment
Standards	IEC 60255-1
Product certifications	GL; UL; CCC; EAC; CE; RCM; CSA
Ambient air temperature for storage	-40…70 °C; -40…70 °C
Ambient air temperature for operation	-20…50 °C at 60 Hz; -20…60 °C at 50 Hz
Relative humidity	93…97 % at 25…55 °C conforming to IEC 60068-2-30
Vibration resistance	0.075 mm (f= 10…58.1 Hz) not in operation conforming to IEC 60068-2-6; 1 gn (f= 10…58.1 Hz) not in operation conforming to IEC 60068-2-6; 0.035 mm (f= 58.1…150 Hz) in operation conforming to IEC 60068-2-6; 0.5 gn (f= 58.1…150 Hz) in operation conforming to IEC 60068-2-6
Shock resistance	15 gn (duration = 11 ms) for not in operation conforming to IEC 60068-2-27; 5 gn (duration = 11 ms) for in operation conforming to IEC 60068-2-27
IP degree of protection	IP20 (terminals) conforming to IEC 60529; IP40 (housing) conforming to IEC 60529; IP50 (front panel) conforming to IEC 60529
Pollution degree	3 conforming to IEC 60664-1
Overvoltage category	III conforming to IEC 60664-1
Dielectric test voltage	2.5 kV, 1 min AC 50 Hz conforming to IEC 60255-27
Insulation resistance	> 100 MOhm at 500 V DC
Connections - terminals	Screw terminals, 2 x 0.5...2 x 2.5 mm² (20 AWG...14 AWG) solid without cable end; Screw terminals, 2 x 0.2...2 x 1.5 mm² (24 AWG...16 AWG) flexible with cable end; Screw terminals, 1 x 0.5...1 x 3.3 mm² (20 AWG...12 AWG) solid without cable end; Screw terminals, 1 x 0.2...1 x 2.5 mm² (24 AWG...14 AWG) flexible with cable end
Tightening torque	0.6…1 N.m conforming to IEC 60947-1
Housing material	Polycarbonate
Mounting support	35 mm DIN rail conforming to IEC 60715
Reliability data	B10d = 290000; MTTFd = 308.2 years
Height	90 mm; 88.9 mm
Width	22.5 mm; 22.9 mm
Depth	73 mm; 73.7 mm
Net weight	0.11 kg; 0.11 kg
Logistical informations
Country of origin	ID
Main
Range of product	Harmony Control Relays
Relay type	Voltage control relay
Product or component type	Voltage control relay
Relay name	RM22UA
Relay monitored parameters	Undervoltage and overvoltage in window mode; Overvoltage or undervoltage detection
Control type	With test button
Contacts type and composition	2 C/O
Network number of phases	1 phase
Supply circuit type	DC
Packing Units
Unit Type of Package 1	PCE
Number of Units in Package 1	1
Package 1 Height	2.6 cm
Package 1 Width	8.2 cm
Package 1 Length	9.5 cm
Package 1 Weight	122.0 g
Unit Type of Package 2	S02
Number of Units in Package 2	40
Package 2 Height	15 cm
Package 2 Width	30 cm
Package 2 Length	40 cm
Package 2 Weight	5.29 kg
Unit Type of Package 3	P06
Number of Units in Package 3	640
Package 3 Height	50.0 cm
Package 3 Width	80.0 cm
Package 3 Length	60.0 cm
Package 3 Weight	92.58 kg

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