[detroiit]

Hello,

I have a titan helios 12 light controller which is wired up to a double pole 80amp breaker and correct gauge wire. My question is I am running the kingbrite 480w which comes with the HLG-480H-48 and driver spec notes that the cold start is 35amps. When powering up say 8-10 of these drivers/lights will the inrush current cause a problem with the breaker? I am assuming no as the breakers can withstand a quick influx of power before tripping. What I'm not able to find is the inrush is a couple ms on the driver but how many ms on a breaker before it trips from an in-rush. For instance if I have 10 drivers cold starting at 350amps does the breaker support the inrush time wise.

Any experience/thoughts?

Thank You.

 

[seharper]

Hello,

I have a titan helios 12 light controller which is wired up to a double pole 80amp breaker and correct gauge wire.

Change that breaker to 50A immediately (which fortunately are only $10). Both the instructions and application diagram (webpage too) specify 50A breaker max, and you should not have ignored that.

The Helios 18 is the one that takes an 80A breaker. I don't think you need it for this light.

My question is I am running the kingbrite 480w which comes with the HLG-480H-48 and driver spec notes that the cold start is 35amps. When powering up say 8-10 of these drivers/lights will the inrush current cause a problem with the breaker? I am assuming no as the breakers can withstand a quick influx of power before tripping. What I'm not able to find is the inrush is a couple ms on the driver but how many ms on a breaker before it trips from an in-rush.

That's all correct so far. The search term you want is "breaker trip curve". If you want the gory details you'll need to go ogle "*your brand name here* breaker trip curve". But they're not all that different one to the next, since UL is the referee that keeps them similar.

Mind you, you must not use brand X breaker in brand Y panel - so don't "brand-shop" looking for a more favorable trip curve. You may use breakers UL-Classified for a competitor panel, but that's limited to Siemens QD and Eaton CHQ and CL.

Breakers have two completely separate trip mechanisms.

- Thermal trip is designed to warm up about as fast as the wires in the walls (not quickly) and trip before the wires overheat. This feature won't even be aware of a 2ms surge.

- Magnetic trip results in instant shutdown at wild overcurrent.

For instance Square D's trip curve for residential breakers <100A claims magnetic trip will not operate below 900% of rated current (which sounds like 1000% +/- 10%). So your 50A breaker is designed to trip at 500A. Square D says this will happen at any time interval down to 5ms. They don't document anything shorter; that's where the log-log graph ends.

Also the 35A spec startup surge may not be so large. That'll be specced for the lowest allowed voltage (90V) you'll be running at almost 3x the voltage so nominally 1/3 the current.

 

[detroiit]

Change that breaker to 50A immediately (which fortunately are only $10). Both the instructions and application diagram (webpage too) specify 50A breaker max, and you should not have ignored that.

The Helios 18 is the one that takes an 80A breaker. I don't think you need it for this light.



That's all correct so far. The search term you want is "breaker trip curve". If you want the gory details you'll need to go ogle "*your brand name here* breaker trip curve". But they're not all that different one to the next, since UL is the referee that keeps them similar.

Mind you, you must not use brand X breaker in brand Y panel - so don't "brand-shop" looking for a more favorable trip curve. You may use breakers UL-Classified for a competitor panel, but that's limited to Siemens QD and Eaton CHQ and CL.

Breakers have two completely separate trip mechanisms.

- Thermal trip is designed to warm up about as fast as the wires in the walls (not quickly) and trip before the wires overheat. This feature won't even be aware of a 2ms surge.

- Magnetic trip results in instant shutdown at wild overcurrent.

For instance Square D's trip curve for residential breakers <100A claims magnetic trip will not operate below 900% of rated current (which sounds like 1000% +/- 10%). So your 50A breaker is designed to trip at 500A. Square D says this will happen at any time interval down to 5ms. They don't document anything shorter; that's where the log-log graph ends.

Also the 35A spec startup surge may not be so large. That'll be specced for the lowest allowed voltage (90V) you'll be running at almost 3x the voltage so nominally 1/3 the current.

@seharper It is the helios 18 (12 light controller) that's why that size breaker it recommends. Overkill for the use of the 480w x 10 leds at 240v for sure only drawing 20amps but it was used before for HID so just decided to use it which I am sure is fine.

It is a square D QO panel/breaker. The spec startup on the meanwell driver shows a 35A cold start using the 240v. But even then should still be good as your saying on the trip curve. I will also pull that up, thank you.

 

[seharper]

@seharper It is the helios 18 (12 light controller) that's why that size breaker it recommends. Overkill for the use of the 480w x 10 leds at 240v for sure only drawing 20amps but it was used before for HID so just decided to use it which I am sure is fine.

It is a square D QO panel/breaker. The spec startup on the meanwell driver shows a 35A cold start using the 240v. But even then should still be good as your saying on the trip curve. I will also pull that up, thank you.

OK if that's the 18 then that's all correct. Square D QO is a good panel. That was the spec I drew from, so your 80A breaker should not magnetic-trip before 720A nominal 800A. That's 4x your expected 175A per bank of 5 lights. (you can control each bank separately by putting them on separate timers, so they startup at slightly different times).

Keep in mind HID was already very, very efficient, nearly as efficient as LED. So reducing your absolute watts significantly may result in less light.

 

[detroiit]

OK if that's the 18 then that's all correct. Square D QO is a good panel. That was the spec I drew from, so your 80A breaker should not magnetic-trip before 720A nominal 800A. That's 4x your expected 175A per bank of 5 lights. (you can control each bank separately by putting them on separate timers, so they startup at slightly different times).

Keep in mind HID was already very, very efficient, nearly as efficient as LED. So reducing your absolute watts significantly may result in less light.

I gotcha and thanks for all the info. Also for that controller if it calls for #4 awg CU or #2AL and an 80amp breaker which is overkill for my setup (only going to be drawing 20amps tops at 240v running) I could use #6 awg wire and a 50 amp breaker and should suffice yes instead of wiring it up for an overkill of 80amps? :glasses:

 

[seharper]

The breaker must protect the downline wire. Since you plan to pull only 4kw x 125% = 5kw, you could use as little as a 30A breaker (7.2kw) if you balance your sides properly. But the wire must match the breaker. You pull off the 60C column of 310.15(B)(16) unless you are running THHN in conduit, then 75C.

30A breaker -> #10 copper cable
40A breaker -> #8 copper cable or wire,
50A breaker -> #6 copper wire, except in conduit/THHN #8 copper is ok
60A breaker -> #6 copper or #4 aluminum (really 55A but you get to round up to the next breaker size)
80A breaker -> #2 Al cable, or #3 Al THHN in conduit, or #4 Cu THHN in conduit