{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"RM4UA33M","brand":"Schneider Electric","brandSlug":"schneider","productSlug":"RM4UA33M","canonicalUrl":"https://aoctrl.com/schneider/RM4UA33M","factsUrl":"https://aoctrl.com/api/mcp/products/RM4UA33M","rawCanonicalId":null},"summary":{"shortDescription":"Schneider Electric Harmony RM4UA33M voltage measurement relay, 2 C/O contacts, adjustable hysteresis 5-30 %, time delay 0.05-30 s, 22.5 mm width, IP20 terminals, EN/IEC 60255-6.","salesMarkdown":"## What the adjustable hysteresis and time delay mean for your protection scheme The RM4UA33M is a voltage measurement relay from the Harmony RM4U series, designed for overvoltage or undervoltage detection per EN/IEC 60255-6. Its adjustable hysteresis of 5 to 30 % of the set threshold prevents nuisance cycling when the monitored voltage hovers near the trip point — set it wide enough to ride through normal line fluctuations but tight enough to catch a sustained deviation. The adjustable time delay, 0.05 to 30 s, lets you coordinate with downstream protection devices. A short delay (0.05 s) catches fast overvoltage events; a longer delay (several seconds) avoids tripping on temporary sags during motor starting or transformer inrush. Two C/O (changeover) output contacts give you independent signalling paths — one for an alarm, one for a trip circuit, for example. The contacts are rated for a minimum switching capacity of 10 mA at 12 V, so they can drive PLC inputs directly without a wetting-current issue. ## Panel fit and environmental ratings The relay occupies 22.5 mm (0.9 in) on a DIN rail — two and a half 9 mm pitches — and is 80 mm deep. That 22.5 mm width is the standard single-module footprint for industrial control relays, so it fits any populated rail without crowding. IP20 on the terminals (finger-safe) and IP50 on the casing means it is suitable for clean, dry indoor panels. Pollution degree 3 per IEC 60664-1 allows operation in environments with conductive pollution, typical of many industrial control cabinets. The relay withstands 15 gn shock for 11 ms and vibration of 0.35 mm at 10-55 Hz per IEC 60068-2-6, so it holds calibration in applications near rotating machinery or conveyors. ## Compliance and documentation The RM4UA33M is designed to EN/IEC 60255-6 (measuring relays and protection equipment) and carries CE marking under the EMC Directive 89/336/EEC and Low Voltage Directive 73/23/EEC. Dielectric test voltage is 2.5 kV, and it withstands a 4.8 kV non-dissipating shock wave. Electromagnetic compatibility is verified to IEC 61000-4-2 (6 kV contact / 8 kV air discharge, level 3) and IEC 61000-4-4 (2 kV fast transients, level 3). Conducted and radiated emissions meet CISPR 11 Group 1 Class A and CISPR 22 Class A.","metaTitle":"Schneider Electric RM4UA33M Voltage Measurement Relay, 2 C/O","metaDescription":"Schneider Electric RM4UA33M Harmony voltage measurement relay, 2 C/O contacts, adjustable hysteresis 5-30%, time delay 0.05-30 s, 22.5 mm wide.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["General Purpose Relays"],"specifications":{"Depth":"3.1 in (80 mm)","Width":"0.9 in (22.5 mm)","Height":"3.07 in (78 mm)","Category":"22376-RELAYS-MEASUREMENT(RM4)","Standards":"EN/IEC 60255-6","Directives":"89/336/EEC - electromagnetic compatibility 73/23/EEC - low voltage directive","Hysteresis":"5...30 % adjustable voltage threshold setting","Relay Type":"Voltage measurement relay","Relay name":"RM4U","Time Delay":"Adjustable 0.05...30 s","9 Mm Pitches":"2.5","Output contacts":"2 C/O","lifecycle_stage":"current","Number of cables":"2","Pollution degree":"3 IEC 60664-1","Range of Product":"Harmony Relay","Shock resistance":"15 gn 11 ms IEC 60068-2-27","Contacts material":"90/10 silver nickel contacts","Relative humidity":"15...85 % 3K3 IEC 60721-3-3","Tightening torque":"5.3...9.7 lbf.in (0.6...1.1 N.m)","Output relay state":"Tripped if A measured > A set","Vibration resistance":"0.35 ms (f= 10...55 Hz) conforming to IEC 60068-2-6","Mechanical durability":"30000000 cycles","Nbr. of units in pkg.":"1","Connections - terminals":"Screw terminals, 2 x 1.5 mm²flexible with cable end Screw terminals, 2 x 2.5 mm²flexible without cable end","Dielectric test voltage":"2.5 kV","IP degree of protection":"IP20 IEC 60529 terminals) IP50 IEC 60529 casing)","Power consumption in VA":"2.7...3.4 VA AC","Switching capacity in mA":"10 mA 12 V","Internal input resistance":"1111000 Ohm 11110000 Ohm 668000 Ohm","Maximum switching voltage":"440 V AC","Product or Component Type":"Industrial measurement and control relays","Non-dissipating shock wave":"4.8 kV","Relay monitored parameters":"Overvoltage or undervoltage detection","Operating Voltage Tolerance":"0.85...1.1 Uc","Contacts type and composition":"2 C/O","Electromagnetic compatibility":"Electrostatic discharge - test level: 6 kV level 3 (contact discharge) conforming to IEC 61000-4-2 Electrostatic discharge - test level: 8 kV level 3 (air discharge) conforming to IEC 61000-4-2","Resistance to fast transients":"2 kV IEC 61000-4-4 level 3","Disturbance radiated/conducted":"CISPR 11 group 1 - class A CISPR 22 - class A","Terminals description ISO n°1":"(C-B2-B3)CO (15-16-18)OC (25-26-28)OC (A1-A2)CO","[Ie] rated operational current":"2 A 158 °F (70 °C) 24 V DC-13 IEC 60947-5-1/1991 2 A 158 °F (70 °C) 24 V DC-13 VDE 0660 3 A 158 °F (70 °C) 115 V AC-15 IEC 60947-5-1/1991 3 A 158 °F (70 °C) 115 V AC-15 VDE 0660 3 A 158 °F (70 °C) 24 V AC-15 IEC 60947-5-1/1991 3 A 158 °F (70 °C) 24 V AC-15 VDE 0660 3 A 158 °F (70 °C) 250 V AC-15 IEC 60947-5-1/1991 3 A 158 °F (70 °C) 250 V AC-15 VDE 0660 0.1 A 158 °F (70 °C) 250 V DC-13 IEC 60947-5-1/1991 0.1 A 158 °F (70 °C) 250 V DC-13 VDE 0660 0.3 A 158 °F (70 °C) 115 V DC-13 IEC 60947-5-1/1991 0.3 A 158 °F (70 °C) 115 V DC-13 VDE 0660","Permissible continuous overload":"400 V 550 V","Protection against electric shocks":"2 kV level 3 IEC 61000-4-5","Ambient Air Temperature for Storage":"-40...185 °F (-40...85 °C)","Permissible non repetitive overload":"500 A 550 A 0.1 Uc","Resistance to electromagnetic fields":"9.1 V/m (10 V/m) IEC 61000-4-3 level 3","Ambient air temperature for operation":"-4...149 °F (-20...65 °C)","Resistance to electrostatic discharge":"6 kV contact IEC 61000-4-2 level 3 8 kV air IEC 61000-4-2 level 3","[Ith] conventional free air thermal current":"8 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$599.53","priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://www.se.com/ie/en/product/RM4UA33M/voltage-measurement-relay-rm4u-range-30-500-v-220-240-v-ac/","alternativesUrl":"https://aoctrl.com/api/mcp/products/RM4UA33M/alternatives.json"},"ai":{"faq":[{"question":"What compliance documentation does Schneider provide for the RM4UA33M?","answer":"The relay is designed to EN/IEC 60255-6 and carries CE marking under the EMC and Low Voltage Directives. EMC test levels include IEC 61000-4-2 (6 kV contact / 8 kV air discharge) and IEC 61000-4-4 (2 kV fast transients). Emissions meet CISPR 11 Group 1 Class A and CISPR 22 Class A."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/schneider/RM4UA33M","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/schneider/RM4UA33M when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}