For low voltage lighting, electricians typically install one or more GFI outlets at outdoor locations near the 12V transformers. The lighting installer will design and install the system under the assumption that the GFI's will deliver the expected 120 volts.
It's sometimes the case, however, that the 120v side drops as much as 10v under the lighting load. Is there a tool or piece of equipment that can be used to predict voltage loss at the GFI under a set amperage load?
For example, an installer would know that his system will apply about 8 amps. He would take this tool, plug it into the GFI, dial it up to 8 amps, then measure the voltage. This would also help predict potential overloads at the breaker box.
Side question, if you see a big voltage drop at the GFI under reasonable loads, does that mean that the GFI was installed with under-rated wire (or daisy-chained wirring instead of pigtails with GFI's in series)? If so, any way to calculate that from load/voltage drop?
Thanks (and note, I'm not suggesting that non-electricians do any work on the 120v side, it would just be helpful for them to know when a GFI is suspect and to predict what voltage taps to use on the low voltage side).
It's sometimes the case, however, that the 120v side drops as much as 10v under the lighting load. Is there a tool or piece of equipment that can be used to predict voltage loss at the GFI under a set amperage load?
For example, an installer would know that his system will apply about 8 amps. He would take this tool, plug it into the GFI, dial it up to 8 amps, then measure the voltage. This would also help predict potential overloads at the breaker box.
Side question, if you see a big voltage drop at the GFI under reasonable loads, does that mean that the GFI was installed with under-rated wire (or daisy-chained wirring instead of pigtails with GFI's in series)? If so, any way to calculate that from load/voltage drop?
Thanks (and note, I'm not suggesting that non-electricians do any work on the 120v side, it would just be helpful for them to know when a GFI is suspect and to predict what voltage taps to use on the low voltage side).