AC Power cord attachment to DC power supply

[SCALDWELL]

I am going to need to attach a simple AC power cord (NEMA 5-15P to standard ROJ power cord P/N 10W1-10106) which is a simple basic commercial off the shelf / COTS 3 wire 18 gauge power cord. I am going to attach this power cord to a Cisco power supply model PWR-IE50W-AC. It has a 3 screw terminal barrier strip with a clear plastic cover over it for safety. My question simply is this, am I required (by the UL/NFPA/NEC codes) to install a ring / spade terminal (using the approved crimp tool to install the ring terminal) onto the ends of the stripped wires before installing them under the screws on the terminal barrier strip? The only other way would be to wrap the (pre-tinned) stranded copper wire under the screws and tighten. Please let me know if you can help me answer this question or point me in the right direction as far as where this is specifically covered in the regulations / codes. Many thanks!

 

[dkidd]

It appears to have box terminals.

 

[Adamjamma]

if it is like the ones I have used to supply power over internet before, you simply strip the wire and put it in the slot, then tighten the screw.. no tinning needed...

 

[SceneryDriver]

I am going to need to attach a simple AC power cord (NEMA 5-15P to standard ROJ power cord P/N 10W1-10106) which is a simple basic commercial off the shelf / COTS 3 wire 18 gauge power cord. I am going to attach this power cord to a Cisco power supply model PWR-IE50W-AC. It has a 3 screw terminal barrier strip with a clear plastic cover over it for safety. My question simply is this, am I required (by the UL/NFPA/NEC codes) to install a ring / spade terminal (using the approved crimp tool to install the ring terminal) onto the ends of the stripped wires before installing them under the screws on the terminal barrier strip? The only other way would be to wrap the (pre-tinned) stranded copper wire under the screws and tighten. Please let me know if you can help me answer this question or point me in the right direction as far as where this is specifically covered in the regulations / codes. Many thanks!

DO NOT tin the wires before wrapping around the screw or placing under the box terminal, if you choose not to use a crimp terminal. We had a series of intermittent failures on some power supplies a few years ago, and it turns out the leads that came attached to the power supplies came with tinned leads. Those pre-tinned ends were creeping under the pressure of the terminal clamps, and coming loose. The solder was cold-flowing, near as we could tell. We started cutting off the tinned ends, re-stripping, and applying ferrules. We had no failures after we started doing that.

My advice is to use fork terminals. It's going to be a better connection. And don't skimp on the crimper either; get a good ratcheting, controlled-cycle tool, and not some cheeseball $3 crimper/stripper/pasta maker from Harbor Fright! tools.


SceneryDriver

 

[Jraef]

Pasta maker? I knew there had to be some use for those things... they’re certainly useless as electrical tools!

I agree though, use some fork tongue terminals and be safe about it.

Side note: UL doesn’t care... unless the terminals specifically SAY that you must use ONLY ring or fork terminals.

 

[jumper]

Side note: UL doesn’t care... unless the terminals specifically SAY that you must use ONLY ring or fork terminals.

Yep. I can terminate a stranded conductor just as well a solid one.

Terminals are for rookies IMO unless spec says different.