Why shouldn't the Mains Ground connect to the Reservoir cap negative?

[Helmholtz]

Just to add:
Crimping a pre-tinned stranded conductor is not considered safe.
Reasoning is that solder tends to creep under pressure making the connection unreliable over time.

[Chuck H]

Well I'd like to know more. The AC ground lead from the cord is not tinned strand. Is it still wrong to solder it to the terminal after crimping? I'm unclear about the "creep under pressure" too. The terminal is bolted down but the crimped, soldered connection to it would not be under the bolt.

[Helmholtz]

Is it still wrong to solder it to the terminal after crimping? .

I don't think so.

I'm unclear about the "creep under pressure" too. The terminal is bolted down but the crimped, soldered connection to it would not be under the bolt.

It's about the crimping pressure.

[Chuck H]

I solder after crimping. I never would have thought to solder and then crimp. That doesn't make sense to me. I hope that clarifies it if that was the consideration. My thinking was that the solder would reinforce the connection and help to keep the connection from oxidizing. I could just use the anti ox paste instead if that would be better.?.

[Greg_L]

I solder after crimping. I never would have thought to solder and then crimp. That doesn't make sense to me. I hope that clarifies it if that was the consideration. My thinking was that the solder would reinforce the connection and help to keep the connection from oxidizing. I could just use the anti ox paste instead if that would be better.?.

Exactly. I solder after crimp too. In my years of wiring motorhomes and race cars I learned that sometimes you have to crimp, and when you do, it's good to reinforce and seal the connection with solder. Motorhomes are a total bitch to work on so you wanna do it once and only once and never look at it again. And with race cars...well you'd hate to lose a race due to a stupid electrical connection. Blowing an engine to pieces is acceptable, but a wiring problem? No bueno.

[Helmholtz]

I solder after crimping. I never would have thought to solder and then crimp. That doesn't make sense to me. I hope that clarifies it if that was the consideration.

No, it wasn't meant as a direct reply to your post.
Just reminded me of this other possible safety issue I learned about when dealing with safety standards.

Dunno if there's something wrong with soldering after crimping. Have done that myself occasionally.
Just prevent flux from getting on the lug.

[Tom Phillips]

I don't believe the following has yet been mentioned in this thread.

Never attach the safety ground under a power transformer bolt! Not the bare wire nor the wire connected to a crimped (soldered or not). There are two issues:
1: As has already been mentioned, the safety ground will be disturbed if the power transformer is changed.
2: Power transformer bolts are notorious for working their way loose. My theory is that this is because of the repetitive heating and cooling cycles as well as the continuous low level 50-60 Hz vibration.

[g1]

I solder after crimping. I never would have thought to solder and then crimp. That doesn't make sense to me.

As far as the 'never solder before crimp', it may seem evident, but might be overlooked with things like screw terminal connections or output binding posts.
If it's an AC plug with screw terminals and the wires are pre-tinned, the crushing action compromises the connection, same as with a crimp.

[Tom Phillips]

As far as the 'never solder before crimp', it may seem evident, but might be overlooked with things like screw terminal connections or output binding posts. If it's an AC plug with screw terminals and the wires are pre-tinned, the crushing action compromises the connection, same as with a crimp.

I encountered an example of this when someone complained that the replacement plug on their household vacuum cleaner was very warm to the touch after normal use. At first I suspected that they had a worn out loose wall socket. The replacement plug was a high quality commercial part but when I looked inside I found that the stranded wire leads had been solder tinned before assembly. Re-terminating the connections using bare copper wire ends completely solved the problem. Another one of those first hand experiences that insure that one will not forget the lesson learned.