Insights
INSIGHTS | How does it work?
Lamp test: everything you need to know.
The lamp test is a system that allows you to check the operation of a pilot light without interfering with its signalling function. Technically, it involves supplying the pilot light with a secondary circuit. In practical terms, by closing the secondary circuit (for example, with a pushbutton or a selector), you can verify if the pilot light has any illuminating issues.
What is the integrated lamp test function (LT)?
Integrated lamp test function means that the lamp test circuit, complete with suitable protection diodes, is integrated into the device itself. This simplifies the installation process because you can enable the lamp test function by simply connecting the lamp test circuit’s related cable, directly to the device!
Thanks to the integrated lamp test function, DOMO devices simplify the installation procedure, saving time and materials for the installer and taking up less space in the electrical panel.
Why does the DOMO integrated lamp test circuit have protection diodes?
Just like in the primary power circuit, DOMO devices provide a diode for protection against voltage feedback due to excess current (backfeed protection), for the integrated lamp test circuit as well. This ensures that the power supplied through the lamp test circuit is also protected against any voltage feedback, minimizing the risk of accidental LED activation and potential hazards to the electrical equipment.
You can check the voltage values of the protection diodes in the "Diodes voltage values" section at the end of each category section in DOMO's catalogues.
What is the double integrated lamp test function (2LT)?
“Double” means that the device is equipped with 2 LT terminals and 2 COM- terminals, which can be useful if you plan to connect your devices in series, allowing you to test them all together.