CHAPTER 4: CONTROLS
2 KHZ INVERTER WEDLING POWER SUPPLY
4-6
990-057
Firing Switch Operation
The Power Supply can use: (a) a Single Pole, Single Throw Switch (SPST); (b) a Single Pole, Double
Throw (SPDT 3-wire) Switch; or (c) an Optical Switch as an input signal to indicate when the Weld Head
has applied the proper force to the parts. Weld Heads with single pole Firing Switches should be
connected to the Mechanical Firing Switch Connector. A 3-Wire Switch or Optical Firing Switch, either
of which should be connected to the Optical Firing Switch Connector, eliminate switch bounce, which
causes false triggering, and should be used when the welding speed exceeds 1.5 welds per second.
MECHANICAL FIRING SWITCH Cable
1
The Mechanical Firing Switch Cable is 5
feet long, Type 2/C, 600 volt cable and
contains 2 shielded, twisted 22 AWG
conductors of high-flex stranded wire.
The Firing Switch Connector is a 2-pin
Amphenol 80-MC2FI (AWTA Part # 520-
011), with strain relief that mates with an
Amphenol 80-MC2M (AWTA Part # 520-
001). Pin 2 is Digital Ground.
2
Connect an AMADA WELD TECH Weld
Head Firing Switch, reed relay, or the open
collector of an opto-coupler to the Foot
Switch connector to initiate weld current.
The emitter of the opto-coupler must be
Figure 4-5. Mechanical Firing Switch
connected to Digital Ground, Pin 2.
OPTICAL FIRING SWITCH Connector
The Optical Firing Switch Connector is a 5 pin TE
Connectivity 212044-1 (AWTA Part # 550-064)
bulkhead connector and mates with an TE
Connectivity Assembly consisting of a TE
Connectivity 212437-3 Plug, 212435-7 Ferrule and
212800-1 Strain Relief. The Optical Firing Switch
can be used in two configurations for initiating a
welding process: a) Single Pole Double Throw
(SPDT 3-wire); or b) Opto-coupler.
Figure 4-6. Wire Firing Switch
