OK, I'm familiar with those single-point grounding panel protection devices.
How about a service panel protector for home use? And a service panel protector for a small (200A) 3-phase panel? I ask, rather than simply Google for it, because Google could come up with some units that are not good. Chuck WB2EDV ----- Original Message ----- From: "Jeff DePolo" <j...@broadsci.com> To: <Repeater-Builder@yahoogroups.com> Sent: Wednesday, June 09, 2010 1:13 PM Subject: RE: [Repeater-Builder] MOVs for power supply primary > > Hmmm. That's a tougher one. Mostly I use the Polyphasers (PLDO-120US-15A > or -20A) at sites that don't have facility-wide protection. The TrippLite > Isobar Ultra series is another (ISOBAR8ULTRA et al). The Isobars also > have > a $50,000 equipment warranty (can't say I've ever had to use it, don't > know > how much red tape there is to go through). I like the Polyphasers because > it's designed to mount to a ground panel/bus bar, so I mount it to the bus > bar that has all of my other arrestors (coax, telco, etc.) on it to > provide > a common-point ground. The Isobar doesn't have provisions for direct > grounding - it relies only on the equipment grounding conductor in the AC > cord, but the TrippLite has arguably better EMI/RFI filtering than the > Polyphaser. > > --- Jeff WN3A > > >> -----Original Message----- >> From: Repeater-Builder@yahoogroups.com >> [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey >> Sent: Tuesday, June 08, 2010 4:48 PM >> To: Repeater-Builder@yahoogroups.com >> Subject: Re: [Repeater-Builder] MOVs for power supply primary >> >> >> >> OK, I should have been more specific. What would be a >> reasonable unit for a >> repeater site that may have only a couple thousand dollars worth of >> equipment inside? >> >> Chuck >> WB2EDV >> >> ----- Original Message ----- >> From: "Jeff DePolo" <j...@broadsci.com <mailto:jd0%40broadsci.com> > >> To: <Repeater-Builder@yahoogroups.com >> <mailto:Repeater-Builder%40yahoogroups.com> > >> Sent: Tuesday, June 08, 2010 4:22 PM >> Subject: RE: [Repeater-Builder] MOVs for power supply primary >> >> > >> > Probably the ones I've had the most luck with are the >> Islatrol series from >> > Control Concepts. I think they have been bought out by >> Emerson or Liebert >> > or one of the other companies that have power divisions. >> Anyway, they >> > call >> > these "active tracking filters". They not only are TVSS's >> but also filter >> > noise, low-amplitude spikes, etc. Right now I'm typing from >> a mountaintop >> > site (broadcast) that we re-built a few years ago. We put >> in an Islator >> > I-2100 (120/240V single-phase). The old equipment shelter >> which had been >> > here since 1990 had the same model unit. In the 15+ years we've been >> > managing and maintaining the site, we've had zero >> surge-related failures, >> > and this site sticks out like a sore thumb as far as >> lightning goes. In >> > the >> > last few years I've used the same series of arrestors for >> new site builds >> > at >> > a dozen sites or so and have had no power-related problems. >> > >> > Others that make comparable-quality products include >> Joslyn, Transtector, >> > and Innovative Technologies. >> > >> > There is one big difference (to me anyway) between TVSS's, >> that being >> > whether they are the series or parallel type. Series type takes the >> > utility >> > service (or transfer switch output if there's a generator >> too) as its >> > input, >> > and provides a protected output to feed the panel(s). >> Parallel type is >> > typically connected to a breaker in the panel, which puts >> it in parallel >> > with all of the loads. I much prefer series. Parallel type >> can be less >> > effective because a) there will always be some inductance >> and resistance >> > in >> > the wiring between the panel and the protector, b) if the >> TVSS conducts, >> > there's a good chance it will trip the breaker in the >> panel, resulting in >> > no >> > protection until the breaker is reset, and c) they are much >> less effective >> > as a noise filter. The upside to parallel type is they can >> easily be >> > added >> > at any time just by popping breakers in the panel and feeding the >> > arrestor. >> > Series, on the other hand, are in-line with the service >> conductors, so if >> > you want to add one (or repair one), you have to take the >> service down. >> > Series tends to also be more expensive, especially for >> three-phase and >> > unlike parallel type, the price goes up as the current >> rating goes up for >> > obvious reasons. >> > >> > A good 200A single-phase arrestor of the ilk I'm talking >> about starts at >> > about $1000 and goes up quite a ways from there. I think these >> > single-phase >> > I-2100's were in the $2000 range. I recently spec'ed a >> 120/208 3-phase >> > Transtector (parallel type) for another site where I'm much >> less concerned >> > about power-wise, and that was about $1800. No cheap, but >> where you're >> > protecting equipment in the 6 and 7 figure range, it's a >> no-brainer. If >> > you're repeater is a Micor mobile and an Astron, it might be hard to >> > justify... :-) >> > >> > --- Jeff >> >> >> >> >> > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > -------------------------------------------------------------------------------- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.829 / Virus Database: 271.1.1/2928 - Release Date: 06/09/10 14:35:00
