SR 2ZH A 23 3 3 X S2 S A. K K2 PROTECT SR 2ZH Dimensions Two-hand module to DIN EN 574 (997) type III C Plug-in terminals 2 safety enabling outputs feedback output with NC function (floating contact) Electronic fuse Installed width: 22.5 mm Green LED displays for relays K and K2 X2 S22 S2 A2. A2 24 4 32 Dimensions 22.5 x x 2 mm Type designation Operating voltage 24 VDC Enabling paths 2 NO/ NC SR 2ZH Test symbol (in preparation) H C D FRG USA CAN 44 Schmersal Industrial switching systems
Circuit example L ** ** A A. A2. S S2 S2 S22 X X2 3 23 3 F3 F F2 Control logic K K K2 K2 H2 A2 4 24 32 SR 2ZH N M 3 N 2-channel control with two contacts A and The NC contact of the buttons A and must have opened before the NO contact closes. No overlapping contacts since otherwise the fuses F and F2 would trigger. Power level: 2-channel control, suitable for contact amplification and contact multiplication through contactors or relays with positively driven contacts. S = feedback loop The control circuit detects wire breaks and earth leakage in the monitoring circuit. Schmersal Industrial switching systems 45
2 Technical data SR 2ZH Operating voltage 24 VDC 5%/+%, residual ripple max. % Fuse of operating voltage internal electronic fuse F, F2, tripping current >.2 A, internal electronic fuse F3, tripping current >.6 A Power consumption Switching capacity of the enabling contacts Fuse of the enabling contacts Switching capacity of the auxiliary contacts Fuse of the auxiliary contacts max..2 W 23 VAC, 6 A ohmic (inductive with suitable suppressor circuit) 6 A slow-blowing 24 VDC, 2 A 2 A slow-blowing Utilisation categories AC 5/DC 3: EN 6 947-5- Pickup delay Dropout delay Contact material/contacts Contact resistance Air clearance and creepage distance Cable connections Dimensions Weight Ambient operating temperature Mechanical life 5 ms 3 ms AgSnO, self-cleaning, positively driven max. mohm in new state DIN VDE - (4.97), 4 kv/2 Plug-in self-lifting screw terminals min..2 mm 2, max. 2.5 mm 2, strand or multicore with wire end ferrule h/b/d mm/22.5 mm/2 mm 2 g 25 C... 45 C (derating curve upon request) 7 switching cycles Terminal markings DIN EN 5 5/DIN 5 3 Operating voltage U Two-hand button A The diagram refers to the potentials at the terminals of the module Two-hand button The diagram refers to the potentials at the terminals of the module NC contact (S) NO contact (S2) NC contact (S2) NO contact (S22) Simultaneity monitoring t (synchronous actuation) Feedback loop X-X2 Output contacts 3/4, 23/24 isolated S t S undisturbed operating cycle Error in feedback loop Synchronous actuation t >.5 s Error button A, before U on 46 Schmersal Industrial switching systems
3 Selection of applications Start/sensor configuration Two-hand circuit to DIN EN 574 and EN 6 24- Malfunctions of every button contact as well as earth and cross shorts are detected. Feedback loop: the safety-related function of external positively driven contactors is monitored by a series circuit of the NC contacts with the terminals X and X2. In release state this circuit must be closed. Safety category III C to DIN EN 574 (2.97) 24 VDC VDC A A. A2. A2. A. X A A2 S S2 S2 S22 X2 Circuit example control level/ two hand circuit to DIN EN 574 and EN 6 24- Malfunctions of every button contact as well as earth and cross shorts are detected. Feedback loop: the safety-related function of external positively driven contactors is monitored by a series circuit of the NC contacts with the terminals X and X2. In release state this circuit must be closed. Safety category III C to DIN EN 574 (2.97) 24 VDC VDC A X S S2 S2 S22 X2 Schmersal Industrial switching systems 47
3 Selection of applications Actuator configuration Single-channel control Suitable for contact amplification or contact multiplication by means of relay or contactor with positively driven contacts. * Feedback loop If the feedback loop is not required it is to be replaced by a bridge. L * X X2 3 4 N Dual-channel control Suitable for contact amplification or contact multiplication by means of relay or contactor with positively driven contacts. * Feedback loop If the feedback loop is not required it is to be replaced by a bridge. L * X X2 3 4 N 48 Schmersal Industrial switching systems
4 Safety relay modules Terminal designation Terminal designation Voltages A A2 Inputs A./S A2./S2 A./S22 A2./S2 +24 VDC VDC Input st actuator (NC contact) Input st actuator (NO contact) Input 2nd actuator (NO contact) Input 2nd actuator (NC contact) Outputs 3/4 First safety enabling output (STOP ) 23/24 Second safety enabling output (STOP ) 3/32 Auxiliary NC output Schmersal Industrial switching systems 49