Troubleshooting Luminaires

heater is operating, shows approximately 4 A of current, this indicates the heater is working properly, because:

I p E or 1000 240 4.16 A

But an ampere reading much different from 4 A (either higher or lower) indicates some fault in either the heater or the branch circuit supplying it. Recording Ammeters

A clamp-on ammeter shows instantaneous current, at a moment in time. But often when troubleshooting electrical equipment and systems, it is more useful to have a record of current over a period of time. Figure 1-2 shows a recording ammeter used for this

1-2 Recording ammeter. 5