Oh, but it entirely depends on the electrical inspector and his interpretation of the rules, Jeff!
There was a big write up in Radio World 15-20 years ago when stations in LA could not get their installation passed by the inspector because the transmitter was not UL listed. Some 200 amp 3 phase plugs and receptacles later, the transmitter could be used as I recall reading the story.
This saga has been ongoing for many years. Someday, someone will get the NFPA to add a broadcast transmitters exemption to the NEC, I hope.
Ron Huckeby, CBRE
From: Jeff Welton [mailto:email@example.com]
Sent: Sunday, July 23, 2017 9:43 PM
To: CRTech <firstname.lastname@example.org>
Subject: Re: [CRTech] Electrical Inspection
The short answer, based on what I've been told in the past, is that if it's industrial equipment (which applies to broadcast transmitters), UL certification isn't required. That's not to say it hasn't changed recently, or won't at some point in the future. However, for the half dozen times I've had customers asking for UL certification, that's been the response. Keeping in mind, I haven't been the guy answering the phones at 3am for over 10 yrs now. :D
On Sat, Jul 22, 2017 at 2:15 AM, John Stortz <email@example.com> wrote:
Interesting question, Steve. Something I had not even thought about.
We did a total rebuild of one station: New tower, new building, plus major road improvement. There were contractors for the building & tower, etc. Whether any of it required permitting or & inspection, I don't know. Later, I replaced a CCA transmitter with a new 30KW BE, and added an older 25KW Sparta for a backup. I guess I just followed the Bill Clinton Policy: "Don't ask / Don't tell." It was way out in a rural farming area. Never heard if there were inspections required for any of it.
In an earlier move, we moved a station into a facility with a common FM panel antenna, designed for up to four 100KW stations. We were the second station to move in. For that move, a self-declared "Broadcast Consultant" oversaw the entire move. We were required to have our own power feed. The inspector didn't like the idea of multiple power feeds going into one building. Our power could be disconnected outside the front door, but the first station's main disconnect was inside their room, on the very back of the room. The only way to turn off their power from outside, would be for us to install a remote-triggered SCR device, which would throw a short circuit across their load, tripping their main breaker. The other station was not interested in going off the air while such equipment was installed. And if their breaker did trip, a backup generator would pick up the load, anyway.
This became an impasse that may have never been resolved. The inspector Red-Tagged our electrical panel. Our so-called "Broadcast Consultant" managed to get the power company to turn the power on "For temporary testing," that lasted for many years. To my knowledge, nothing was ever resolved. The SCR equipment was never installed at the panel for the other station. After about 5 years of operation, I remover the red tag & tossed it, a couple years before we sold the station & it was relocated to another site.
*Politics is the gentle art of getting votes from the poor and campaign funds from the rich, by promising to protect each from the other.
On Thu, Jul 20, 2017 at 11:31 PM, Mark Croom <firstname.lastname@example.org> wrote:
This was a topic of conversation some years ago, basically that one interpretation of the NEC would require that anything HARD WIRED into the electrical system would need to be UL listed.
The most common solution I'm aware of was to wire the circuit to outlets that had adequate outlets on them (Cam-Lock connectors being the most likely to work as I recall). You get the inspection done and wire the AC input of the transmitter to the Cam-Locks so it becomes a "plug-in" device.
This may be tricky with high power three phase but there's got to be a way to do it that satisfies the inspector.
I've never encountered this so I'm just repeating what I recall from years gone by.
On Wed, Jul 19, 2017 at 1:42 PM, Steve Tuzeneu <email@example.com> wrote:
When you have installed a new transmitter and have a local inspector ask for you UL sticker or certificate on your transmitter, how did you handle this?
What did you give your local inspector?
We gave our inspector a letter from Nautel, and said he would send it off to UL.
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