Square D Class 9999 Type S Auxiliary Contact for NEMA Motor Starters, Sizes 00 to 7

Square D Class 9999 Type SX auxiliary contacts, the external side-mounting contact kits for Square D NEMA Type S motor starters and contactors in sizes 00 through 7. These are the full-size industrial starters found in compressor room panels and motor control centres.

Fit one of these when you need the panel to know what the motor is actually doing. The contact block mounts on the side of the starter and is driven directly off the armature, so it follows the main contacts exactly. That is the signal you wire to a run light, an hour meter, a lead and lag sequencer, a dryer run interlock or a remote monitoring input. It is a far better answer than a current switch clamped on a load conductor, and it is the only answer that still works when the motor is running unloaded.

Part reference

• AUX-N6: Square D 9999SX6, one normally open contact
• AUX-N8: Square D 9999SX8, one normally open and one normally closed isolated contact

Key specifications

• Class 9999, Type SX external auxiliary contact kit
• Rating: 10 A continuous, 600 V maximum
• Make 60 A and break 6 A at up to 120 V; 7200 VA make and 720 VA break from 120 to 600 V
• Field convertible: the contact can be changed between normally open and normally closed in the field
• Mounts externally on Class 8536 starters, Class 8502 contactors and Class 8903 lighting contactors, NEMA sizes 00 through 7
• Screw clamp terminals

Field convertible, and the isolated pair

Both kits are field convertible, so a contact ordered as normally open can be reconfigured to normally closed on the bench without a different part. The difference that matters between them is the second contact on the SX8 and the fact that it is isolated: the two contacts share no common terminal, so you can run them on separate circuits at different voltages without tying the two together. If you are signalling a 120 V run light from the control transformer and a 24 V input on a controller at the same time, the SX8 is the one to fit.

These are the NEMA starter contacts, not the definite purpose ones

The SX series mounts on NEMA Type S starters, the ones whose nameplate gives a NEMA size rather than an amp rating. If your contactor is a definite purpose unit rated 20 A to 90 A, you need the Class 9999 Type D contacts instead, which the Warthog Air Compressor Store also stocks.

Square D Class 9999 Type S auxiliary contacts for NEMA motor starters, part numbers 9999SX6 and 9999SX8, supplied by AirComParts through the Warthog Air Compressor Store alongside replacement starter coils, overload relays and pressure switches for compressor control panels.