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Starting Member


Wednesday, October 25th 2017, 7:31pm

Low Voltage Lighting Question

I have a very long run and would like help optimizing. I have two 300W transformers in one 600W unit.
I have a 290' run, 325' run and a 250' run. I can connect the 290 and 325 into a loop if I add 35' to create one big 650' run (apparently it only counts as half run for calculations). I only have light loads. 66W on the 290' run. 66W on the 325' run. 77W on the 250' run.

Can someone figure out my optimal layout? Options include
- combine 290 and 325 runs into a loop?
- combine 250' and 290' runs into a V?
All my options exceed the recommended allowances. I don't know how critical it is to abide by these?
My voltage drop on the combined 650' run with only 130W is likely too high according to the formula.

Thank you in advance to any genius who can help me.


Supreme Member

Posts: 482

Location: Houston, Texas


Thursday, October 26th 2017, 4:09pm

A lot of this depends on your cable gauge.
A thicker cable will allow you more flexiblity.

It may also make sense to understand if you are using LED or Halogen.

You may want to use LED to help with your situation.

In my experience it is critical to follow the transformer specs to avoid tripping the transformer. :)
:thumbup: :thumbsup:
LI0006121, BPAT0011021, CI0009500


Supreme Member

Posts: 5,307

Location: Metro NYC


Tuesday, October 31st 2017, 1:29pm

Are there any primary-connection options? Some lighting transformers might have a split-wired primary to accommodate input voltages slightly higher or lower than norm.

All said and done, upgrading your output wiring is the simplest approach.

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