Amp Draw

[Eric2.0]

I did the math(hopefully correct) and found that just one light(alley) drew 3.48 AMPS with my Multi Meter testing for current. I then added all the lights together at 3.48 amps x 15 lights total for about a 55 Amp draw if the bar was full on. This is a Vista with 5 rotators, takedowns, alley left/right, sweeps, rear and front flashers. I'm just trying to verify that I am right, or in the ballpark to how many amps these things use while full on. So am I in the ballpark? This is the first time I found out how to test current in a circuit and testing a light bar so I'm not real confident in my findings. It seems like a lot of amp draw.

 

[Da-Sarge]

55A sounds about rite for a bar equipped with 55W bulbs with 35W allys and takedowns and 35W sweeps plus motor drives what bulb types are used? Some bars run H1 halogens 3.6A @ 12v on 55w bulbs the bayonet based bulbs whelen and federalsignal often use are usually 35W but some are 55W

Take a look at the bulbs and run the amp measurements on a single rotator if possible if you have a meter with an amp clamp turn on the full bar and do some measurements that should be your best option

 

[Sparky_911]

Sounds about right. Rule of thumb is 5-10amp per rotor, 3-5amp per TD/ALLEY for halogen bars.

 

[Pete L.]

amps = watts divided by volts.
H1 bulbs are 50w, 795 bulbs are 50w and 796 bulbs are 35w.

 

[Jarred J.]

If the vehicle is running it's 13.8 not 12.

 

[Jennifer Rose Towing]

The federal signal website should have manual with specifications on it for that bar. Did you pick a Vista over the Value Bar?