Relays & Sockets RU Series Universal Relays Key features: * * * * * * * * * * * Full featured universal miniature relays Designed with environment taken into consideration Two terminal styles: plug-in and PCB mount Non-polarized LED indicator No internal wires, lead-free construction Cadmium-free contacts Mechanical flag indicator Manual latching lever with color coding for AC or DC coil Snap-on yellow marking plate; optional marking plates are available in four other colors Maximum contact ratings: 10A (RU2), 6A (RU4), 3A (RU42) UL Recognized, CSA Certified, EN Compliant EN61810-1 With Latching or Momentary Lever Latching and Momentary Lever Using the lever, operation can be checked without energizing the coil. The lever is color coded for AC and DC coils. Mechanical Indicator* The contact position can be confirmed through the five small windows. Marking Plate Standard yellow marking plate is easily replaced with optional marking plates in four colors for easy identification of relays. Latching Momentary AC coil: Orange Red DC coil: Green Blue In Normal Operation LED Indicator* Non-polarized green LED indicator is standard provision for plug-in terminal, latching lever types Note: Turn off the power to the relay coil when using the latching lever. After checking the operation, return the latching lever in the normal position. Standard (without lever) AC/DC Color Marking For identification of AC or DC coils. AC coil: Yellow DC coil: Blue Coil Voltage Tape Color 24V AC White Marking Plate 100 to 110V AC Clear LED Indicator* Non-polarized green LED indicator is standard provision for plug-in terminal types. 110 to 120V AC Blue 200 to 220V AC Black Mechanical Indicator* Circuit Breakers Terminal Blocks Contactors Timers Relays & Sockets Signaling Lights Switches & Pilot Lights RU AC Coil DC Coil Red 24V DC Green 6V DC 12V DC 48V DC *Not available on PCB type. 790 220 to 240V AC 110V DC www.IDEC.com Voltage marking on yellow tape Relays & Sockets RU Switches & Pilot Lights Part Number Selection Part Number Contact Model DPDT (10A) With Momentary Lever Standard RU2S-C-0 RU2S-0 RU2S-M-0 A24, A110, A220 D6, D12, D24, D48, D110 With RC (AC coil only) RU2S-CR-0 RU2S-R-0 RU2S-MR-0 A110, A220 With diode (DC coil only) RU2S-CD-0 RU2S-D-0 RU2S-MD-0 D6, D12, D24, D48, D110 PCB RU2V-NF-0 -- -- A24, A110, A220 D6, D12, D24, D48, D110 Standard RU4S-C-0 RU4S-0 RU4S-M-0 A24, A110, A220 D6, D12, D24, D48, D110 With RC (AC coil only) RU4S-CR-0 RU4S-R-0 RU4S-MR-0 A110, A220 With diode (DC coil only) RU4S-CD-0 RU4S-D-0 RU4S-MD-0 D6, D12, D24, D48, D110 PCB RU4V-NF-0 -- -- A24, A110, A220 D6, D12, D24, D48, D110 Standard RU42S-C-0 RU42S-0 RU42S-M-0 A24, A110, A220 D6, D12, D24, D48, D110 With RC (AC coil only) RU42S-CR-0 RU42S-R-0 RU42S-MR-0 A110, A220 With diode (DC coil only) RU42S-CD-0 RU42S-D-0 RU42S-MD-0 D6, D12, D24, D48, D110 PCB RU42V-NF-0 -- -- A24, A110, A220 D6, D12, D24, D48, D110 1. Plug-in terminal models have an LED indicator and a mechanical indicator as standard. 2. PCB models do not have an LED indicator or a mechanical indicator. Relays & Sockets 4PDT Bifurcated (3A) With Latching Lever Signaling Lights 4PDT (6A) Coil Voltage Code (Standard Stock in bold) Standard Ordering Information When ordering, specify the Part No. and coil voltage code: Part No. A110 Timers (example) RU2S-C Coil Voltage Code Coil Voltage Table Coil Voltage Code Coil Rating A24 A110 A220 D6 D12 D24 D48 D110 24V AC 110-120V AC 220-240V AC 6V DC 12V DC 24V DC 48V DC 110V DC Sockets Spring Clamp DIN Rail Mount Standard DIN Rail Mount Finger-safe DIN Rail Mount RU2S (DPDT) SU2S-11L SM2S-05 SM2S-05C RU4S (4PDT) RU42S (4PDT) SU4S-11L SY4S-05 SY4S-05C Panel Mount SY4S-51 Contactors Relays PCB Mount SM2S-61 SM2S-62 SY4S-61 SY4S-62 Terminal Blocks Circuit Breakers 800-262-IDEC (4332) * USA & Canada 791 Relays & Sockets Hold Down Springs & Clips Appearance Signaling Lights Switches & Pilot Lights RU Item Relay For DIN Mount Socket For Through Panel & PCB Mount Socket Pullover Wire Spring RU2S/RU4S/ RU42S SY4S-02F1 SY4S-51F1 Leaf Spring (side latch) RU2S/RU4S/ RU42S SFA-202* SFA-302* Leaf Spring (top latch) RU2S/RU4S/ RU42S SFA-101* SFA-301* Note: Order 2 pieces for each relay Relays & Sockets Accessories Name Part Number Color Code * Marking Plate RU9Z-P* A (orange), G (green), S (blue), W (white), Y (yellow) Specify a color code when ordering. The marking plate can be removed from the relay by inserting a flat screwdriver under the marking plate. Specifications Model (Contact) Contact Material Timers Contact Resistance RU2 (DPDT) RU4 (4PDT) RU42 (4PDT-bifurcated) Silver alloy Silver (gold clad) Silver-nickel (gold clad) 50 m maximum 1 Minimum Applicable Load 2 24V DC, 5 mA (reference value) 1V DC, 1 mA Operating Time 3 20 ms maximum Release Time 3 20 ms maximum 1V DC, 0.1 mA Power Consumption AC: 1.1 to 1.4VA (50 Hz), 0.9 to 1.2VA (60 Hz) DC: 0.9 to 1.0W Insulation Resistance 100M minimum (500V DC megger) Terminal Blocks Contactors Between contact and coil: 2500V AC, 1 minute Dielectric Strength 2500V AC, 1 minute 2000V AC, 1 minute Between contacts of the same pole: 1000V AC, 1 minute Operating Frequency Electrical: 1800 operations/h maximum Mechanical: 18,000 operations/h maximum Vibration Resistance Damage limits: 10 to 55 Hz, amplitude 0.5 mm Operating extremes: 10 to 55 Hz, amplitude 0.5 mm Shock Resistance Mechanical Life Damage limits: 1000 m/s2 (100G) Operating extremes: 150 m/s2 (15G) AC: 50,000,000 operations DC: 100,000,000 operations 50,000,000 operations Electrical Life 4 See table on page 794 Operating Temperature 5 PCB model: -55 to +70C (no freezing) Blade model: -55 to +60C (no freezing) Operating Humidity Circuit Breakers Between contacts of different poles: Weight 5 to 85% RH (no condensation) Approx. 35g 1. Measured using 5V DC, 1A voltage drop method 2. Measured at operating frequency of 120 operations/min (failure rate level P, reference value) 3. Measured at the rated voltage (at 20C), excluding contact bouncing; Release time of AC relays with RC: 25 ms maximum Release time of DC relays with diode: 40 ms maximum 792 4. Contact Load and Electrical Life (at ambient temperature 20C) 5. Measured at the rated voltage. www.IDEC.com Relays & Sockets RU Item Appearance Use with Part No. Remarks All DIN rail sockets BNDN1000 DIN Rail End Stop DIN rail BNL5 9.1 mm wide. Replacement Hold-Down Spring Anchor Horseshoe clip for DIN rail sockets Y778-011 For use on DIN rail mount socket when using pullover wire hold down spring. 2 pieces included with each socket. Signaling Lights Aluminum DIN Rail (1 meter length) The BNDN1000 is designed to accommodate DIN mount sockets. Made of durable extruded aluminum, the BNDN1000 measures 0.413 (10.5mm) in height and 1.37 (35mm) in width (DIN standard). Standard length is 39" (1,000mm). Switches & Pilot Lights Accessories Coil Ratings Rated Voltage (V) DC 50 Hz 60 Hz Coil Resistance () 10% (at 20C) 24 A24 49.3 42.5 110-120 A110 8.4-10.0 7.1-8.2 4,550 220-240 A220 4.2-5.0 3.6-4.2 18,230 Operating Characteristics (values at 20C) Maximum Continuous Applied Voltage Pickup Voltage Dropout Voltage 110% 80% maximum 30% minimum 110% 80% maximum 10% minimum Relays & Sockets AC (50/60 Hz) Rated Current (mA) 15% (at 20C) Coil Voltage Code 164 6 D6 155 40 12 D12 80 160 D24 44.7 605 D48 18 2,560 110 D110 8.9 12,100 Timers 24 48 1. The rated current includes the current of the LED indicator. Surge Suppressor Ratings UL and c-UL Ratings Model With Diode Diode reverse voltage: 1000V Diode forward current: 1A Voltage DPDT 4PDT 4PDT bifurcated 10A 6A 3A RU2 RU4 RU42 RU2 RU4 RU42 250V AC 10A -- 3A -- 6A -- -- 1/10HP -- 30V DC 10A 6A 3A -- -- -- -- -- -- Rated Load Resistive Load Inductive Load Voltage (V) 2500VA AC 1250VA AC 250 AC 10A Res. Load Ind. Load 5A 300W DC 150W DC 30 DC 10A 5A 1500VA AC 600VA AC 250 AC 6A 0.8A 180W DC 90W DC 30 DC 6A 1.5A 750VA AC 200VA AC 250 AC 3A 0.8A 90W DC 45W DC 30 DC 3A 1.5A TUV Ratings Resistive RU42 Voltage Resistive Inductive RU2 RU4 RU42 RU2 RU4 RU42 250V AC 3A 250V AC 10A 6A 3A 5A 0.8A 0.8A 30V DC 3A 30V DC 10A 6A 3A 5A 1.5A 1.5A Circuit Breakers 1. On 4PDT relays, the maximum allowable total current of neighboring two poles is 6A. At the rated load, make sure that the total current of neighboring two poles does not exceed 6A (3A + 3A = 6A). 2. Inductive load for the rated load -- cos o = 0.3, L/R = 7 ms 800-262-IDEC (4332) * USA & Canada Terminal Blocks Contact Allowable Contact Power Horse Power Rating RU42 Voltage Maximum Contact Capacity General Use RU4 CSA Ratings Contact Ratings Continuous Current Resistive RU2 Contactors With RC RC series circuit R: 20 k, C: 0.033 F AC Coil DC Coil Ratings 793 Relays & Sockets Socket Specifications DIN Rail Mount Sockets Through Panel Mount Socket PCB Mount Socket Sockets Terminal Electrical Rating Wire Size SU2S-11L Spring clamp terminals 250V/10A 24-16 AWG SU4S-11L Spring clamp terminals 250V/6A (using RU4), 10A (using RU2) 24-16 AWG SM2S-05 M3 screw with captive wire clamp 300V, 10A Maximum up to 2-#14AWG 5.5 - 9in*lbs SM2S-05C M3 screw with captive wire clamp, fingersafe 300V, 10A Maximum up to 2-#14AWG 5.5 - 9in*lbs SY4S-05 M3 screw with captive wire clamp 300V, 7A (using RU4), 10A (using RU2) Maximum up to 2-#14AWG 5.5 - 9in*lbs SY4S-05C M3 screw with captive wire clamp, fingersafe 300V, 7A (using RU4), 10A (using RU2) Maximum up to 2-#14AWG 5.5 - 9in*lbs SY4S-51 Solder 300V, 7A -- -- SY4S-61 PCB mount 300V, 7A -- -- SY4S-62 PCB mount 250V, 7A -- -- RU2 (Resistive Load) RU4 (Resistive Load) ( 10,000 operations) 100 10 Timers 1 0.1 0.5 1 5 10 0.1 1 3 0.02 6 AC: cos o = 0.3 DC: L/R = 7 ms 100 1 5 10 1 10 Load Current (A) 0.02 0.1 10 AC: cos o = 0.3 DC: L/R = 7 ms 0.5 Load Current (A) 1 0.02 0.1 RU4 RU42 (Bifurcated) AC resistive AC inductive (cos o = 0.3) 10 Load Current (A) 5 1 0.1 DC resistive DC inductive L/R = 7 ms 10 30 100 250 500 Load Voltage (V) 794 www.IDEC.com 0.5 Load Current (A) Maximum Switching Current RU2 1 100 AC: cos o = 0.3 DC: L/R = 7 ms 0.5 0.5 Load Current (A) 250V AC 30V DC 110V DC ( 10,000 operations) 10 0.1 RU42 (Inductive Load) 250V AC 30V DC 110V DC ( 10,000 operations) ( 10,000 operations) 0.5 RU4 (Inductive Load) 100 0.1 10 Load Current (A) RU2 (Inductive Load) 1 100 1 1 10 Load Current (A) 1000 Contactors -- 250V AC 30V DC 110V DC 100 250V AC/30V DC 110V DC Terminal Blocks -- RU42 (Resistive Load) 250V AC 30V DC 110V DC 1000 1000 ( 10,000 operations) Relays & Sockets 250V AC 30V DC 110V DC Circuit Breakers Torque Electrical Life Curves ( 10,000 operations) Signaling Lights Switches & Pilot Lights RU 3 6 Relays & Sockets RU RU2 (AC Coil, 60 Hz) 120 110 110 100 100 100 90 90 90 80 Load current 10A 2 poles 70 60 50 40 Load current 5A 2 poles 20 Load current 10A 2 poles 70 60 50 40 20 Load current 5A 2 poles 10 20 30 40 50 60 0 70 10 RU4/RU42 (AC Coil, 50 Hz) 20 30 40 60 50 40 50 Ambient Temperature (C) 60 70 0 RU4/RU42 (AC Coil, 60 Hz) 100 90 90 90 50 40 30 Load current 3A 4 poles Load current 6A 2 poles 60 50 40 20 Load current 3A 4 poles 20 30 40 50 Ambient Temperature (C) 60 70 0 20 70 30 40 50 60 70 50 60 70 Load current 6A 2 poles 60 50 40 20 No load current 10 40 Load current 3A 4 poles No load current 10 60 70 0 10 Ambient Temperature (C) 20 30 40 50 Timers 10 30 80 30 10 10 0 80 30 No load current 20 Temperature Rise (C) 100 Temperature Rise (C) 110 100 60 20 Relays & Sockets 120 110 70 10 RU4/RU42 (DC Coil) 110 Load current 6A 2 poles No load current Ambient Temperature (C) 120 70 Load current 5A 2 poles 10 120 80 Load current 10A 2 poles 70 20 No load current Ambient Temperature (C) 80 30 10 10 0 80 30 No load current Temperature Rise (C) 120 110 Temperature Rise (C) 120 30 Temperature Rise (C) RU2 (DC Coil) Signaling Lights Temperature Rise (C) RU2 (AC Coil, 50 Hz) Switches & Pilot Lights Ambient Temperature vs. Temperature Rise Curves Ambient Temperature (C) The above temperature rise curves show the characteristics when 100% the rated coil voltage is applied. The heat resistance of the coil is 120C. The slant dashed line indicates the allowable temperature rise for the coil at different ambient temperatures. Load current 6A x 2 poles is for the RU4 models only. Contactors Terminal Blocks Circuit Breakers 800-262-IDEC (4332) * USA & Canada 795 Relays & Sockets Internal Connection (View from Bottom) RU2S-* Standard (1)12 (5)14 (9)11 (13)A1 RU2S-*R with RC RU2S-*D With Diode (1)12 (4)42 (5)14 (8)44 (14)A2 Signaling Lights (5)14 (1)12 (4)42 (9)11 (13)A1 (14)A2 (13)A1 Relays & Sockets RU4S-*/RU42S-* Standard RU4S-*R/RU42S-*R With RC (3)32 (4)42 (1)12 (7)34 (8)44 (5)14 (9)11 (10)21 (11)31 (12)41 (2)22 (6)24 (3)32 (5)14 (6)24 (7)34 (14)A2 Timers (3)32 (4)42 (1)12 (7)34 (8)44 (5)14 (2)22 (6)24 (13)A1 24V DC coil or less (1)12 (2)22 (7)34 (8)44 (5)14 (6)24 (3)32 (4)42 (7)34 (8)44 (9)11 (10)21 (11)31 (12)41 (14)A2 (14)A2 (13)A1 Mechanical Indicator Window Marking Plate (yellow) Latching Lever Orange RU2SAC: DC: Green Over 24V DC coilMarking Plate (yellow) LED Indicator (green) Color Marking Dimensions (mm) AC: Yellow DC: Blue RU2V Marking Plate Removal Slot 0.5 35.0 Marking Plate Removal Slot 13.2 o1.2 2.2 Hole 21.0 14 6.4 12 9 5 13 4 8 1 2.6 21.0 Terminal Blocks 0.8 2.6 4.0 0.5 0.5 27.5 27.5 Mounting Hole Layout 7.0 oles 1H 8-o 13.2 Marking plate removal slot is provided only on one side. Insert a flat screwdriver into the slot to remove the marking plate. 4.1 6.4 12.7 Circuit Breakers All dimensions in mm. 796 www.IDEC.com (3)32 (7)34 (4)42 (8)44 (9)11 (10)21 (11)31 (12)41 (14)A2 (13)A1 (14)A2 (13)A1 RU4S-*D/RU42S-*D With Diode RU4V-NF-*/RU42V-NF-* (9)11 (10)21 (11)31 (12)41 (3)32 (4)42 Over 24V AC/DC coil Contactors (14)A2 (5)14 (6)24 (8)44 (9)11 (10)21 (11)31 (12)41 (9)11 (10)21 (11)31 (12)41 (13)A1 (12)41 (1)12 (2)22 (4)42 24V AC/DC coil or less (1)12 (2)22 (8)44 Over 24V DC coil Over 24V AC/DC coil (13)A1 (4)42 (5)14 (8)44 (12)41 (5)14 (6)24 (14)A2 24V DC coil or less (9)11 (1)12 (2)22 (12)41 (13)A1 24V AC/DC coil or less (1)12 (8)44 (9)11 (12)41 RU2V-NF-* (4)42 35.0 Switches & Pilot Lights RU (14)A2 Relays & Sockets Mechanical Indicator Window Marking Plate (yellow) Color Marking LED Indicator (green) Latching Lever AC: Orange RU4S/RU42S DC: Green RU Marking Plate (yellow) Switches & Pilot Lights Yellow Dimensions con'tAC: (mm) DC: Blue RU4V/RU42V 0.5 35.0 Marking Plate Removal Slot 35.0 Marking Plate Removal Slot 4.0 6.4 14 8 12 0.8 2.6 o1.2 x 2.2 Hole 13 10 9 21.0 11 4 6 5 7 2 1 3 21.0 3-4.4 0.5 2.6 Signaling Lights 0.5 27.5 27.5 Marking plate removal slot is provided only on one side. Insert a flat screwdriver into the slot to remove the marking plate. Mounting Hole Layout 7.0 o1 es Hol Relays & Sockets 6.4 12.7 4.1 4.4 13.2 14- All dimensions in mm. Spring Clamp DIN Rail Mount Sockets SU2S-11L SU4S-11L 31 Terminal Arrangement 2-o3.2 Mounting Holes 9 8 5 4 1 14 13 28.8 (Top View) 2-o3.2 Mounting Holes 7 6 5 4 3 2 1 37.5 80 Ring terminals cannot be used. 14 32 38.3 4.4 28.8 24.0 9 8 Ring terminals cannot be used. 13 (Top View) Contactors 32 38.3 4.4 Terminal Arrangement 12 11 10 37.5 80 24.0 12 Standard DIN Rail Mount Sockets 31.5 6 M3 Terminal Screw 8 25 4.8 min. 14 13 12 9 45 26 o3.2 min. Terminal Arrangement 8 4 7 6 3 2 5 1 26 4 max. 4.8 min. 14 13 12 11 10 9 18.5 (Top View) 5.9 max. 2-o4.2 Mounting Holes (or M4 Tapped Holes) 1 4.2 4 max. DIN Rail (BNDN) 5 62 4 18 26 4.2 26 30 Terminal Arrangement 2-o4.2 Mounting Holes (or M4 Tapped Holes) 18.5 3 DIN Rail (BNDN) Terminal Blocks M3 Terminal Screw 0.7 18 3 6 45 30 SY4S-05 31.5 62 0.7 SM2S-05 Timers 31 25 (Top View) 5.9 max. o3.2 min. Circuit Breakers 800-262-IDEC (4332) * USA & Canada 797 Relays & Sockets Dimensions con't (mm) Finger-safe DIN Rail Mount Sockets SM2S-05C SY4S-05C 6 30 DIN Rail (BNDN) 35.5 25 M3 Terminal Screw 2-o4.2 Mounting Holes (or M4 Tapped Holes) 18 5 4 1 o5.5 26 46 DIN Rail (BNDN) Terminal Arrangement 2-o4.2 Mounting Holes (or M4 Tapped Holes) 18 64 8 25 8 7 6 5 4 3 2 1 26 14 Ring terminals cannot be used. 14 13 12 9 (Top View) 2 29 (Top View) 29 PCB Mount Sockets SM2S-62 21.2 15 21.2 4.1 (Bottom View) 9-o2 holes (Tolerance 0.1) * 17.2 min. when using a hold-down spring. ** 13.2 min. when using a hold-down spring for the relay with check button. 13.2 13.8 min. (Bottom View) 11 1.5 15 15-o2 holes (Tolerance 0.1) 1.5 Through Panel Mount Socket SY4S-51 3 11 18.7 2.4 [27 (N-1) + 21.4] + 0.5 0 13 14 0 25.6 1 2 3 4 5 6 7 8 9 10 11 12 +0.2 Terminal Arrangement (Bottom View) N: No. of sockets mounted 5.4 min.* 27 0.3 31 25.4 Panel Thickness: 1 to 2 4.1 16.8 10.4 (Bottom View) 3 15-o2 holes 11 * 19.2 min. when using hold-down springs 21.2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1.4 0.3 21.2 1.4 15 29 16.8 9 10.4 Terminal Arrangement * 10.4 min. when using hold-down springs Circuit Breakers 21.2 www.IDEC.com 12.2 min.* 3 14.2 min.* 27 0.3 31 25.4 1 2 3 4 5 6 7 8 9 10 11 12 13 14 4.4 4.1 Terminal Arrangement 8.2 min.** 8.8 4.4 9 Timers SY4S-62 8.8 Contactors 9 16.8 10.4 4 8 12 14 15 1.5 13.2 798 8.2 min.** 11 SY4S-61 Terminal Blocks 1 5 9 13 (Tolerance 0.1) * 19.2 min. when using hold-down springs 1.5 3 9-o2 holes 1.4 11 0.3 29 9 4.1 10.4 Terminal Arrangement (Bottom View) 14.2 min.* 3 13.2 13.8 min. 12.2 min.* 0.3 27 13.2 4 8 12 14 16.8 25.4 1 5 9 13 1.4 Terminal Arrangement 31 Relays & Sockets SM2S-61 13 12 11 10 9 Ring terminals cannot be used. 18.2 26 1.6 18.2 2 26 1.6 Signaling Lights 64 4.2 o5.5 35.5 M3 Terminal Screw 6 Terminal Arrangement 46 30 4.2 Switches & Pilot Lights RU (Tolerance 0.1) * 17.2 min. when using a hold-down spring. * *13.2 min. when using a hold-down spring for the relay with check button Relays & Sockets Operating Instructions Driving Circuit for Relays Protection for Relay Contacts 1. To ensure correct relay operation, apply rated voltage to the relay coil. 1. The contact ratings show maximum values. Make sure that these values are not exceeded. When an inrush current flows through the load, the contact may become welded. If this is the case, connect a contact protection circuit, such as a current limiting resistor. Pulsation Smoothing Capacitor + - Emin Emax R Relay Ripple Factor (%) DC Emean Emax - Emin Emean 2. Contact protection circuit: When switching an inductive load, arcing causes carbides to form on the contacts, resulting in increased contact resistance. In consideration of contact reliability, contact life, and noise suppression, use of a surge absorbing circuit is recommended. Note that the release time of the load becomes slightly longer. Check the operation using the actual load. Incorrect use of a contact protection circuit will adversely affect switching characteristics. Four typical examples of contact protection circuits are shown in the following table: 100% IncorrectCorrect TE R R R Ind. Load RC C This protection circuit can be used for both AC and DC load power circuits. R: Resistor of approximately the same resistance value as the load C: 0.1 to 1 F Diode 3. Leakage current while relay is off: When driving an element at the same time as the relay operation, special consideration is needed for the circuit design. As shown in the incorrect circuit below, leakage current (Io) flows through the relay coil while the relay is off. Leakage current causes coil release failure or adversely affects the vibration resistance and shock resistance. Design a circuit as shown in the correct example. Power + Power D Ind. Load - Varistor Varistor Power C Power C Power Load Load Contactors - R Relay This protection circuit can be used for both AC and DC load power circuits. For a best result, when using a power voltage of 24 to 48V AC/DC, connect a varistor across the load. When using a power voltage of 100 to 240V AC/DC, connect a varistor across the contacts. 3. Do not use a contact protection circuit as shown below: Back emf suppressing diode + Ind. Load This protection circuit can be used for DC load power circuits. Use a diode with the following ratings. Reverse withstand voltage: Power voltage of the load circuit x 10 Forward current: More than the load current Timers Io 4. Surge suppression for transistor driving circuits: When the relay coil is turned off, a high-voltage pulse is generated, causing a transistor to deteriorate and sometimes to break. Be sure to connect a diode to suppress the back electromotive force. Then, the coil release time becomes slightly longer. To shorten the coil release time, connect a Zener diode between the collector and emitter of the transistor. Select a Zener diode with a Zener voltage slightly higher than the power voltage. This protection circuit can be used when the load impedance is smaller than the RC impedance in an AC load power circuit. * R: Resistor of approximately the same resistance value as the load * C:0.1 to 1 F Relays & Sockets Emax = Maximum of pulsating current Emin = Minimum of pulsating current Emean = DC mean value Signaling Lights 2. Input voltage for the DC coil: A complete DC voltage is best for the coil power to make sure of stable relay operation. When using a power supply containing a ripple voltage, suppress the ripple factor within 5%. When power is supplied through a rectification circuit, the relay operating characteristics, such as pickup voltage and dropout voltage, depend on the ripple factor. Connect a smoothing capacitor for better operating characteristics as shown below. Switches & Pilot Lights Operating Instructions This protection circuit is very effective in arc suppression when opening the contacts. But, the capacitor is charged while the contacts are opened. When the contacts are closed, the capacitor is discharged through the contacts, increasing the possibility of contact welding. Generally, switching a DC inductive load is more difficult than switching a DC resistive load. Using an appropriate arc suppressor, however, will improve the switching characteristics of a DC inductive load. Terminal Blocks This protection circuit is very effective in arc suppression when opening the contacts. But, when the contacts are closed, a current flows to charge the capacitor, causing contact welding. Soldering Circuit Breakers 1. When soldering the relay terminals, use a soldering iron of 30 to 60W, and quickly complete soldering (within approximately 3 seconds). 2. Use a non-corrosive rosin flux. 800-262-IDEC (4332) * USA & Canada 817 Relays & Sockets Relays & Sockets Signaling Lights Switches & Pilot Lights Operating Instructions Operating Instructions con't Other Precautions 2. UL and CSA ratings may differ from product rated values determined by IDEC. 1. General notice: To maintain the initial characteristics, do not drop or shock the relay. The relay cover cannot be removed from the base during normal operation. To maintain the initial characteristics, do not remove the relay cover. 3. Do not use relays in the vicinity of strong magnetic field, as this may affect relay operation. Use the relay in environments free from condensation, dust, sulfur dioxide (SO2), and hydrogen sulfide (H2S). Make sure that the coil voltage does not exceed applicable coil voltage range. Safety Precautions * Turn off the power to the relay before starting installation, removal, wiring, maintenance, and inspection of the relays. Failure to turn power off may cause electrical shock or fire hazard. * Observe specifications and rated values, otherwise electrical shock or fire hazard may be caused. * Use wires of the proper size to meet voltage and current requirements. Tighten the terminal screws on the relay socket to the proper tightening torque. * Before operating the latching lever of the RU relay, turn off the power to the RU relay. After checking the circuit, return the latching lever to the original position. * Do not use the latching lever as a switch. The durability of the latching lever is a minimum of 100 operations. * When using DC loads on 4PDT relays, apply a positive voltage to terminals of neighboring poles and a negative voltage to the other terminals of neighboring poles to prevent the possibility of short circuits. * DC relays with a diode have a polarity in the coil terminals. Apply the DC voltage to the correct terminals. Circuit Breakers Terminal Blocks Contactors Timers * Surge absorbing elements on AC relays with RC or DC relays with diode are provided to absorb the back electromotive force generated by the coil. When the relay is subject to an excessive external surge voltage, the surge absorbing element may be damaged. Add another surge absorbing provision to the relay to prevent damage. Precautions for the RU Relays 818 www.IDEC.com