Fluorescent lights

[Jimmyb]

hi all, I have asked this before but still not sure, when calculating v.d on fluorescent/discharge circuits do you include the 1.8 factor in the calc or is this just for cable current rating

e.g is it like motors where you are allowed a bigger vd on startup, but size the cable on the rating of the motor.

 

[Guest123]

Hi.

To carry out the VD calc you need first to obtain Ib for the circuit. In order to do that for a discharge lamp circuit you need to use the 1.8 multiplier to obtain a more accurate result.

So it isn't actually used in the calc but is used before.

HTH.