This can happen with the smaller IPBs under certain conditions of mounting surface materials and whether the IPB is mounted vertically or horizontally.The IPBs are normally supplied with a 14 volt lamp. Make sure that you are using 12 to 14 volts to operate the bulb. If you are, we recommend using a #658 bulb Item # 91-1220-10 instead. This is still a 14 volt lamp, but it runs cooler. IPBs can be ordered with the #658 lamps.

The switch connections are made using the NO (Normally Open) and the COM (COMmon) terminals on the switch. COM and NO are marked on the switch. The lamp terminals are the two terminals located nearest the bezel.

Silver contact switches are rated 10 amps, 250 vac. Gold contact switches are rated .1 amp, 250 volts. Our standard switches have silver contacts.

Switch Comparison Chart

The Illuminated Pushbutton Assemblies use a ring a groove method to lock the lampholder assembly into place. When assembled correctly you will feel and hear the assembly snap together.

The Illuminated Pushbutton Assemblies use a ring and groove method to lock the lampholder assembly into place. To disassemble (change lamp) simply grasp the lower portion of the lampholder assembly and bend it up one way or the other, it may take a fairly good amount of force to get the parts to separate.

The buttons themselves are not UL Listed, but the switches and the plastic materials are. Click on the following two links to see a listing of the materials and switches we use:
IPB UL Information

VLT UL Information

To wire a standard push button that has a microswitch with 3 contacts on it please refer to the FAQ on "How do I wire a micro switch".

To wire an illuminated pushbutton, the same FAQ applies with one addition. The other 2 metal contacts that extend from the plastic beneath the button (not part of the switch itself) are the contacts used to illuminate the incandescent lamp or LED that is in the button housing.
In the case of an incandescent bulb you will only need to match the operating voltage of the lamp to an external power supply and connect your positive voltage to one contact (+) and your ground (-) to the other contact. Polarity / the position of which contact is ground (-) and which is positive (+) does not matter.
In the case of using an LED polarity does matter and again you need to match the operating voltage of the LED to your external power supply. In many of the buttons, embossed into the white plastic are a - or + sign. In this case wire your ground to - and your positive voltage to +. If the button does not have these symbols embossed into it then choose one side to be positive + and the other to be -. Check the plastic base of LED for polarity symbols and match those to your wiring. An LED with the polarity revered will not work.
Commonly used incandescent bulbs are # 161 which is a 14v bulb typically operated at 12v dc and a # 555 bulb which a 6.3v bulb typicall operated at 5v dc.