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.