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"High" current @56VDC relay.

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forrestc:
I have a design which currently uses a TX2-3V relay.   Has been a solid performer, but I do occasionally get feedback from customers that they'd like a bit more switching capacity at 48V/56V.  The TX2-3V switches around 1A at this voltage.

I've dug through all of the distributors I normally used and the only PCB mount relay I've found that is better in a meaningful way at this voltage is a G5LE, however it is mechanically too tall - I only have around 0.65" at the absolute maximum.   

For this application, a relay contact is the correct solution, a solid state relay has some shortcomings (including the complexity of doing a normally closed contact).

I'm hoping someone on here has come across a reasonably small relay which will switch around 2A or more (is better) at 56VDC.     And by reasonable sized, I mean something PCB mount and not over 0.65" tall.  Of course inexpensive is a plus since we consume around 1000 of these a year.

And yes, I realize I'm asking for a unicorn....

Zero999:
According to the data sheet, it's DPDT and rated to 2A, as 30V. If you're not using both of the contacts, simply connect them in series and it should be fine at 2A, up to 60V. It's breaking the arc, which is challenging for DC and two contacts in series, will do a better job than one.
https://www.mouser.co.uk/datasheet/2/315/mech_eng_tx-1075670.pdf

Someone:

--- Quote from: Zero999 on July 02, 2019, 08:43:06 am ---If you're not using both of the contacts, simply connect them in series and it should be fine at 2A, up to 60V.
--- End quote ---
Its not always that simple, relays with manufacturer ratings for series operation such as the Schrack RT2 for instance. Its possible to go the other way too and use a lower current relay with both contacts in parallel. Really needs testing on the specific load application.

forrestc:

--- Quote from: Someone on July 03, 2019, 01:32:27 am ---
--- Quote from: Zero999 on July 02, 2019, 08:43:06 am ---If you're not using both of the contacts, simply connect them in series and it should be fine at 2A, up to 60V.
--- End quote ---
Its not always that simple, relays with manufacturer ratings for series operation such as the Schrack RT2 for instance. Its possible to go the other way too and use a lower current relay with both contacts in parallel. Really needs testing on the specific load application.

--- End quote ---

Plus, in this application I need to expose both the normally open and normally closed contacts.   Which is challenging.   I've wondered about doing some odd wiring where you take the common of one pole and wire it to both "throws" of the second pole.    That way the 'common' of the first pole is interrupted briefly by the switching of the second pole between the two poles, hopefully gaining you series wiring.

I've actually looked at the schrack RT2, but wasn't sure about the series wiring with needing both NO and NC contacts.   I tonight noticed they have a latching version available which may actually negate the need for both contacts, but it's pretty pricey.

The Schrack RT2 is one of the few relays I've found which actually states the series wiring rating.   At the voltage we're talking about, it's 2A for a single, but 8A for both in series.  I wish that more relays were rated this way as I might find one that would work for this.   Unfortunately, I'm not particularly willing to pass on a rating which I haven't had verified by a vendor, and we're small enough that asking a vendor to specify something else in their datasheet isn't likely to be result in any useful outcome.

Someone:

--- Quote from: forrestc on July 03, 2019, 07:23:39 am ---
--- Quote from: Someone on July 03, 2019, 01:32:27 am ---
--- Quote from: Zero999 on July 02, 2019, 08:43:06 am ---If you're not using both of the contacts, simply connect them in series and it should be fine at 2A, up to 60V.
--- End quote ---
Its not always that simple, relays with manufacturer ratings for series operation such as the Schrack RT2 for instance. Its possible to go the other way too and use a lower current relay with both contacts in parallel. Really needs testing on the specific load application.

--- End quote ---

Plus, in this application I need to expose both the normally open and normally closed contacts.   Which is challenging.   I've wondered about doing some odd wiring where you take the common of one pole and wire it to both "throws" of the second pole.    That way the 'common' of the first pole is interrupted briefly by the switching of the second pole between the two poles, hopefully gaining you series wiring.

I've actually looked at the schrack RT2, but wasn't sure about the series wiring with needing both NO and NC contacts.   I tonight noticed they have a latching version available which may actually negate the need for both contacts, but it's pretty pricey.
--- End quote ---
Another possibility to look at is a hybrid relay + SSR or roll your own on the board. Or some other similarly sturdy active arc suppression.

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