ZIV 3

[Ali-rashid]

I have just heard of a brand for protection relays and comms solutions with name ZIV. I have not yet worked with their devices and don't know how is their quality. Is anybody familiar with them? How is their quality and level?

 

[davidbeach]

From the North American perspective they’re a third tier supplier, at best. In Spain they’re at the top of the list. Where are you?

 

[Ali-rashid]

Thanks
Iran
In case of protection relays for distribution in Iran usually Vamp, Micom, Fanox are used. But for Oil and Gas sector normally GE, Siemens and ABB are utilized. how does ZIV rank against these?

 

[davidbeach]

Having never seriously looked at ZIV or many of the others listed I can't rank them. I think the drivers in relay selection can be summed up as 1) use something well supported in your area, 2) use as few different brands as you can get away with.

Well supported goes along with widely used. You don't really want to be out on your own if the relay is doing something you don't understand or if it fails. The simpler the relay the less that might matter; a basic overcurrent relay is very different from a full featured line relay. The relays I prefer aren't on your list, suggesting they aren't common or well supported where you are; they probably wouldn't be a good choice there even though here I would rank them at the top of the list.

It takes time and effort to fully understand a relay and its nuances, the fewer you try to understand the better you'll be at doing so. Again, the simpler the relay the less this matters as well. Even with overcurrent relays though you could get unexpected results if you mix relays that operate on fundamental current with those that operate on RMS current. All of one or all of the other and you get the coordination you expect; mix them in an environment with significant harmonic current and the wrong relay could trip first.

It's one thing to stay on top of what's out there, but I certainly wouldn't try new relays just for the sake of trying something new. As I see it relay brand changes are more driven by being pushed away by the present choice than by being pulled in by an alternate choice.

 

[HamburgerHelper]

I would say that sole sourcing likely provides more benefits than using multiple brands. You are exposing yourself to systemic problems but most issues are the result of incorrect settings. SEL's different lines are supposedly developed by different groups so I believe that is them trying to prevent systemic issues from crossing all their lines of relays. For very basic relays, I don't think what you buy really matters. For more complicated microprocessor relays, SEL is hands down the best when it comes to product and support.

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