Need Help with oil pressure safety switch

[camoit]

OK do this then. Get a test light and a battery. hook one post of the battery to any connector of the switch. (I would guess that there is only 3 connectors on it.) On the other battery post hook up your test light wire. Check each post and see witch one lights up the light. That is Normally closed WITH OUT PRESSURE. That only leaves the Normally open and the common to figure out. 20 PSI of air pressure run through a regulator will kick the switch into the other state. Are the 3 prongs all lined up in a row or is there 1 that is off?

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Normally there is one that is out of position like on a relay that will be the com.