This product looks like it will do exactly what I want and for a decent price but it has a 10-12 week lead time.
Does anyone know of anything that would be suitable for switching 56vdc @ 13a without a long lead time or crazy price as I am going to need quite a few of these.
Anything that can switch and allows current to flow both directions would be fine. The options seem to be very limited in this range.
Here’s a relay search that returns in stock, SPST-NO , 12VDC, through hole, non-latching, contacts >= 110VDC @ >= 30A
Thanks for that. I spent ages going through the search.
I am really unsure how I missed all those. I must have just looked at the first part of the rating.
Hi johnau,
The list that @PaulHutch gave has some good options. Keep in mind that the maximum current listed for a relay is typically not at the maximum voltage. One needs to look at the max switching power rating of the of the contacts to get an idea of the max current at any given switching voltage.
For instance, with PTRH-1A-12SF-X, which is listed as a 30A relay and rated for up to 110Vdc, if one looks into the data sheet, one will note that the max “Switching Power” is 900W.
From Picker PTRH-1A-12SF-X datasheet:
Using Ohm’s law, one can calculate the maximum current for any given voltage. So, for a 56V load, the maximum current is about 16A ( I = P/V = 900W / 56V = 16.07A). The closer you get to this maximum rating, the more likely that you’ll accelerate wear on the contacts. If your 13A requirement is not including much margin, then the 16A of this relay is on the low end of what I’d be comfortable with. Additionally, if your current rating does not include inrush current, then I’d definitely look for one of the higher current rated parts in his list.
Thanks for the additional info. I didn’t look at that side of it but I think something like that will still be fine.
The 13a draw was rounded up and at full power. The device will typically be run at a lot lower power than this, I just wanted to ensure there was enough top end room for worst case.
Regarding switching wear, is this a on/off cycle or a constant on? I assume its switch cycles because of the arc generated?
You are correct, the wear comes almost entirely from the switching arc.
