Outdoor ATS

[WoodrowJWeen]

We need to connect an entire existing buiding to a new generator located outside in a weatherproof enclosure. We are thinking that the simple solution is to put the ATS outside between the utility padmount transformer and the new generator. We have done this sucessfully on several projects in the southeast (US). This new project however is in the southwest, near Phoenix. It has been suggested, however that the ATS will get too hot and will malfunction in this heat, even though it will be in a outdoor (NEMA 3R) enclosure. I find it hard to believe that standard outdoor gear that works in Alabama and Florida would be unsuitable for Arizona. Does anyone have any experience with this?

 

[rbulsara]

YOu want to check with the manufactures for the desgined temperature range.

Modern ATS has electronoic controls and PLCs which may be temperature sensitive. You can also ask for a relay based controls which are more forgiving ,if electronics is an issue.

 

[busbar]

 
Offhand, there will be some difference if the enclosure is in direct sunlight versus shaded. I agree with rbulsara—check with ATS manufacturers for their specific characteristics.

 

[amesolutions]

I live in Barbados, here it is always around 31 Deg Celsius.

I have installed a 600 Amp ATS in a Type 3R enclosure between the Genset and the Tx, in the hot blistering Sun.The installation is two years old, and absolutly no problems at all.

I have used the ASCO 300 series switch, which in my opinion, if no logging or any special options are necessary, the 300 series will do just fine.It has minimal circuitry, and is a solenoid solid terminal based switch, that is electrically operated and mechanically held, as opposed to t he contact based relay type switches, which are usually electrically held.

If it is still a problem, I take it that a cooling fan can be installed at the some point of the enclosure, so the weather tightness wont be compromised.Fan would be thermostically controlled of course.See ASCo for the temp. ratings on its 300 series switches.

Regards

 

[GOTWW]

We had an 600A Asco also installed this summer in the mojave desert. Embarrassed to say I never really gave the tempurature much thought, just the standard specs. Almost got burnt, as the ATS needed to be SE listed as the pad-mount did not have a secondary circuit breaker, narrowly missing a change order, by finding this ATS.

 

[WoodrowJWeen]

Have there been any heat related problems?

 

[GOTWW]

None on that unit yet or several cummings ATS systems that have been out in the field much longer for water well B/U.

 

[jraef]

The problem is in the electronics. Most electronic systems are designed around a 50deg C standard (122deg F) for internal air temperature, with a few going to 60deg C (140 F). We run 2 x 1500kW 6.6kV parallel gensets to power up test stands when the utility cannot provide enough during peak use hours in the Las Vegas area. We have had several OT trips on equipment even when the main load was not being run! We recorded internal enclosure temperatures in excess of 160 F by 10AM when in direct sun exposure. That said however, those applications were fine after simply putting a roof overhead to keep the sun off of the enclosures. We have had only 1 OT trip since then, and that was when running on a 120 degree day at 97% load late in the afternoon when the sun angle got under the shed. If your ATS enclosure design takes heat loading from direct sun exposure into account you should be fine. Just keep in mind that NEMA 3R outdoor enclosure specifications say absolutely nothing about sun exposure. That is left up to the equipment design engineers.

"Venditori de oleum-vipera non vigere excordis populi"