Cost Effective Interposing Relays / DC MCBs
Cost Effective Interposing Relays / DC MCBs
(OP)
Greetings
I need the manufacturers names who can provide cost effective Interposing Relays and DC MCBs for Switchgears. Both items shall be UL listed.
Big names offer high prices because of their names. I will appreciate your feedback.
Thanks
I need the manufacturers names who can provide cost effective Interposing Relays and DC MCBs for Switchgears. Both items shall be UL listed.
Big names offer high prices because of their names. I will appreciate your feedback.
Thanks






RE: Cost Effective Interposing Relays / DC MCBs
What do you need from the interposing relay? Clifford & Snell's D series is first class, and although not 'cheap' per se I would say they are cost-effective. Areva's Prima range was also reasonable, although I'm not sure whether it went to Schneider or Alstom after the breakup of Areva.
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RE: Cost Effective Interposing Relays / DC MCBs
RE: Cost Effective Interposing Relays / DC MCBs
rasevskii
RE: Cost Effective Interposing Relays / DC MCBs
As to your "smaller less expensive options", it is a poor criterion for an engineering decision. What you will find is that designing testing and manufacturing a proper DC rated relay is expensive. Then the economies of scale are not there to keep the cost low because they are not nearly as universally used as AC relays. So small companies are not going to be able to afford making "cheaper" versions because they will not sell enough of them to justify the considerable investment.
Just pick a good quality relay that fits your needs and negotiate as good a deal as you can up front, then move on. For something as low volume as Switchgear Control applications, you have likely already wasted more money that you can possibly save just by reading this post.
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RE: Cost Effective Interposing Relays / DC MCBs
I've seen little octal-base plug-in relays used in this application that failed on the first trip.
RE: Cost Effective Interposing Relays / DC MCBs
RE: Cost Effective Interposing Relays / DC MCBs
Contacts welding closed is bad enough but contacts welding closed when trying to open may be worse.
Bottom line: be very careful interrupting DC current.
Bill
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RE: Cost Effective Interposing Relays / DC MCBs
1- very fast , cannot break the DC current to an inductive load.
2- very slow , can break the DC current to an inductive load.