Amada 1-288-01, Operation Manual, Page: 63 / 144

CHAPTER 4: INTRODUCTION TO FEEDBACK MODES AND MONITORING
HF28 DC RESISTANCE WELDING SYSTEM
990-372 4-9
5. Weld Stop
Applications

Part-to-part positioning problems

Electrode-to-part positioning problems
Function
To detect work piece resistance changes that occur when parts are positioned incorrectly at the weld
head. In this case, the energy limits
will prevent blowouts, parts damage, and electrode damage. Limits
can be set to terminate the weld if this occurs.
Description
This function terminates the weld energy during the welding process if pre-set weld
current
,
voltage
, or
power
limits are exceeded. In addition to inhibiting the weld, the Control has four programmable relay
outputs which can be used to trigger alarms to signal operators of weld faults, or signal automation
equipment to perform pre-programmed actions, such as stopping the production line so the faulty weld
piece can be removed.
In the profile above, the weld current is exceeding the selected upper limit before the end of the welding
cycle. The spike in the current waveform indicates that parts were misplaced. In this case, the operator
has selected the option to terminate the weld energy under this condition, so the energy limits monitor
terminates the Pulse 1 weld and inhibits the Pulse 2 weld if it had been programmed.
The monitor measures the weld energy parameters during the weld period and compares the
measurements against the programmed limits.
NOTE:
When using the energy limits monitor, always select a monitor mode that is different from the
feedback mode. For example:

If you are welding in constant current, monitor voltage.

If you are welding in constant voltage, monitor current.

If you are welding in constant power, monitor current or voltage.