Control Inputs.

The Welserv weld timer unit has 16 PNP user configerable input lines which can be configured to perform any of the following functions or can be redefine in standard PLC ladder software to perform any function required by the programmer.

 High Lift  Control line for high lift valve.
 Foot Switch 1  Normaly open switch on foot switch.
 Foot Switch 2  Normaly closed switch on foot switch.
 Push Button 1  Normally open switch from safety relay.
 Push Button 2  Normally closed switch from safety relay.
 External Weld ON/Off  External weld on / off switch.
 Second Stage  Second stage input to hold off weld after Squeeze is complete.

 Thermostat 1 & 2

 Two lines for thermostat to monitor transformer and SCR temprature.
 Emergence Stop  Emergence stop line to abort weld and halt SCR firing.
 BCD Program Select  5 Line of BCD select for remote program sellect.
 Nut Depth Sensor  Input for mechanical switch to detec head over travel if part not present.
 Low Force Sensor  Low force sensor to allow operation of high force valve.
 Interlocking  Interlocking to delay weld firing untill authorisation is given.
 External Alarm Resets  External resets for Tip Dress, Tip Change, Nut Count, Weld Fail etc.
 Feeder Responce 1 & 2  Two lines for nut / bolt feeder responce when feed is complete. 
 Head Back  Sensor input before signal to allow robot or auto welder to move.

Control Outputs.

Ther are 12  PNP outputs which  are pre defined for the following functions but can be reconfigured via standard PLC ladder software to performe any function.

 High Lift Valve  Controls High Lift valve for use with retract cylinder or low force system.
 Weld Air Valve  Controls main welding cylinder.
 Weld Output  Gives signal whren weld is made (signal for duration of weld).
 Pass Output

 Outputs when weld is in tollerance.

 Fail Output  Outputs when weld is out of tollerance.
 End Of Sequence  Output when cycle is complete and head is back.
 Feeder 1 Start  Call for feeder 1 to send nut / stud.
 Feeder 2 Start  Call for feeder 2 to send nut / stud.
 Checking Jig Start  Initiate checking sequence on Poka-Yoke prior to weld being made.
 Weld Request  Request interlocking system for permission to weld.




Welserv (Electronics) Ltd.

Resistance Welding Supplies Ltd.

Unit 1, Waterfall Lane Trading Estate, Waterfall Lane, Cradley Heath, West Midlands, B64 6PU,

Tel. 0121 559 9449.              Fax. 0121 559 7798.

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