SoliForum - 3D Printing Community — Fried Terminal Block Connector - Elec Short

Re: Fried Terminal Block Connector - Elec Short

null@example.com (Krythis) — Sat, 02 Aug 2014 22:48:08 +0000

I'll certainly be checking my screw terminals more often now. New connectors are in and thankfully they were near identical to the last set I bought.

So if anyone is looking for replacements from in the US these work perfectly:

Mouser.com
571-7966342
571-7966382

Re: Fried Terminal Block Connector - Elec Short

null@example.com (IronMan) — Sat, 02 Aug 2014 21:23:13 +0000

adrian wrote:

IronMan wrote:
My bad for not being specific...I meant an SSR (solid state relay)...to me it's a relay. Will try to be more specific
Fair enough - I'm being specific about it because its not just a matter of semantics - they are entirely different physical entities that behave markedly differently designed for different application requirements.

You are absolutely correct! Need specifics especially here...I have been accused of being vague in the past 45 years; I still think of a computer monitor as a CRT...will keep working on that! :-)

Re: Fried Terminal Block Connector - Elec Short

null@example.com (adrian) — Sat, 02 Aug 2014 04:52:29 +0000

IronMan wrote:

My bad for not being specific...I meant an SSR (solid state relay)...to me it's a relay. Will try to be more specific

Fair enough - I'm being specific about it because its not just a matter of semantics - they are entirely different physical entities that behave markedly differently designed for different application requirements.

Re: Fried Terminal Block Connector - Elec Short

null@example.com (IronMan) — Fri, 01 Aug 2014 16:21:38 +0000

My bad for not being specific...I meant an SSR (solid state relay)...to me it's a relay. Will try to be more specific

Re: Fried Terminal Block Connector - Elec Short

null@example.com (adrian) — Fri, 01 Aug 2014 15:55:49 +0000

IronMan wrote:

Not sure on the connectors, but they will probably be fine...
However, have you considered powering the heated with a separate power supply and relay? You could be pushing the limits of your board by running it as is.

Do not use a relay. Use a MOSFET or an SSR (it is designed to operate at the frequencies required for PID (<1ms vs >10ms). A Relay is open to welding either open or closed, and making and breaking mechanically high amp DC loads will kill it right quick. It suffers 'contact bounce' which produces a *ton* of electrical noise - which can show up as all sorts of missed steps and fun things to troubleshoot.

There is a reason you do not see 3D printers shipping with relays - they have enough electrical noise issue what with ATX supplies, dodgy USB cables, exposed electronics with no shielding etc etc. And they are so prone to failure in this sort of environment (high temp, high amp).

All of this also sets aside the horrible racket the ticking relay will cause in PID mode holding setpoint.

I mention this because I've noted you repeatedly suggest the use of a relay - which is entirely inappropriate for anything but the most basic of Bang-Bang bed control - which is then prone to delamination and warpage issue due to the temperature deltas between heat cycles. Please consider this before suggesting it to others as a wise decision.

Re: Fried Terminal Block Connector - Elec Short

null@example.com (IronMan) — Fri, 01 Aug 2014 15:36:20 +0000

A lot of folks are powering off the board, but if your bed is drawing anything over 16A then it is at the brink of what the board can handle...

Still, a loose connection can melt things! I make it a part of my weekly routine to check all screw terminals!

Re: Fried Terminal Block Connector - Elec Short

null@example.com (IanJohnson) — Fri, 01 Aug 2014 15:35:47 +0000

The same thing happened to me with my Sanguinololu, also from turning the printer around too much. I took the opportunity to upgrade to an Azteeg, but when I fried the Azteeg, I replaced the melted connector and got the Sanguino running while waiting for the replacement.

Re: Fried Terminal Block Connector - Elec Short

null@example.com (Krythis) — Fri, 01 Aug 2014 15:28:16 +0000

It's been running for over a year with this set up. No problems until I turned the printer a couple times and removed/reattached wires to remove the wire chain I have been using. When doing so a couple days ago I noticed some discoloration of the connector so I ordered those replacements. I didn't touch the bed wires so I never noticed one was loose until right after taking the pic of the melted connector.

Re: Fried Terminal Block Connector - Elec Short

null@example.com (IronMan) — Fri, 01 Aug 2014 15:05:47 +0000

Not sure on the connectors, but they will probably be fine...

However, have you considered powering the heated with a separate power supply and relay? You could be pushing the limits of your board by running it as is.

Fried Terminal Block Connector - Elec Short

null@example.com (Krythis) — Fri, 01 Aug 2014 14:34:55 +0000

Welp looks like my printer is offline for a while I'm going to look over the machine while I wait for new parts, but from what I've found so far it would appear that the negative wire for the QU-BD bed came loose causing too much current to be drawn. I believe only the connectors are fried as the machine shut down for a couple seconds then fired up and continued to print. I shut down the printer and checked the electrical connection to find the connector had melted.

I ordered the parts below from Mouser.com. Can anyone confirm these are the correct replacements for the connectors purchased from JayCar?
571-7966342
571-7966382