HIgh current terminal blocks
HIgh current terminal blocks
(OP)
Had to replace my water heater timer (again, due to chinesium relays) and went to a different make (DTWH40).
What concerns me is the new unit has terminal blocks as opposed to screw terminals. Unit is rated for 40A resistive load up to 277VAC.
My application is around 30A, was a bit hesitant to install it this weekend after seeing the terminal block connections, need to insert 10AWG stranded copper into them.
My question is- any suggestions regarding high current terminal blocks? Are they safe, should I prep the wires by splaying the individual strands flat before insertion?
Thanks
-AK2DM
What concerns me is the new unit has terminal blocks as opposed to screw terminals. Unit is rated for 40A resistive load up to 277VAC.
My application is around 30A, was a bit hesitant to install it this weekend after seeing the terminal block connections, need to insert 10AWG stranded copper into them.
My question is- any suggestions regarding high current terminal blocks? Are they safe, should I prep the wires by splaying the individual strands flat before insertion?
Thanks
-AK2DM
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"It's the questions that drive us"
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RE: HIgh current terminal blocks
RE: HIgh current terminal blocks
xnuke
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RE: HIgh current terminal blocks
I have had experience with such blocks up to 10A ratings, was a bit concerned using such flora at 30A. Indeed they are scaled up to proportions I have never used before.
I have had half a mind to retrofit the previous failed unit for firing a pair of SSR's in lieu of the chinesium relays which is common to all the previous failed units.
Not surprised that the first Intermatic timer lasted for 12 years, the second for 2 years, the third for a year (warranteed), and the fourth just over a year.
The Tork unit does have a holographic UL label, FWIW.
Will proceed with the install.
Thanks ScottyUK and xnuke
-AK2DM
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"It's the questions that drive us"
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RE: HIgh current terminal blocks
RE: HIgh current terminal blocks
Yes I have large traces on both sides of the board but heating in that area is very..very minimal compared to everywhere else.. Plenty of copper/mass in the actual wires to keep that area cool.
For some reason many companies HATE screw terminals like that.. Some of our customers will not use them at all.. For no good reason though other than they just never have accepted them.. (Old guy mentality.. we've always done it that way so why change)
And no need to do anything but strip the wires, insert and torque down.
RE: HIgh current terminal blocks
RE: HIgh current terminal blocks
A lot of the issues often stem from expecting the terminals to be exactly like the screw type, when they're not. Admittedly, I do not like the push-in tool-less "TopJob" Spring terminals either, but I'm all for the other spring type.
Whether it makes it an 'old guy' argument is debatable, I've met a few 'old guys' who love the spring terminals as well.
RE: HIgh current terminal blocks
RE: HIgh current terminal blocks
RE: HIgh current terminal blocks
Further clicking resulted in seeing that this Tork timer uses terminals rated for up to #8 wire. So use that, not #10. If your heater says it is rated 30A, you can use that to size the wire, but the wire must be sized for 125% of that current rating, so you will need #8.
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: HIgh current terminal blocks
SO I current clamped it out, running 18.7A at 240VAC.
Dual 4500W element heaters, only one element can be on at a time. Breaker is rated at 25A, so 10AWG should suffice.
Went to flush this 2yr old water heater to no avail. It would not drain even with the water inlet feed on, snaked a zip tie into the drain valve and a shotgun like spray of chunks of sediments sprayed out for about 2 seconds and then clogged right up again. After a few reps myself and the surrounding area were covered top to bottom in chunks. I have a few ideas in mind to overcome this....
The old heater lasted 15 years before rusting out with about 7 flushes over that span. Each time it was flushed just a handful of Calgon-like crystal sediments came out. The quantity and quality of the sediments produced by the new heater are a totally different animal, large planar flakes and side-by-side rice grain chunks. Granted, I do live in a hard water town.
Thanks for your inputs, was totally unaware that such style of contact blocks hold up in the 100A range, pretty amazing.
-AK2DM
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"It's the questions that drive us"
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RE: HIgh current terminal blocks
RE: HIgh current terminal blocks
A 5 gallon bucket was half filled with sand/silt/scale,etc...
Then hot water looked like cola for an hour or so after..
It was gross :)
RE: HIgh current terminal blocks
RE: HIgh current terminal blocks