Push Button Pre-Charger On 2 Inverter With Parallel Battery

[Crossy]

OK. But please use Lucar or Faston connectors, don't solder to the switch.

 

 

You would use COM and NO for your pre-charge.

 

[Jan Dietz]

Just wondering if there's an actual need for a push button at all (I understand with the given lowish resistance given), but why not permanently wire in a 1K or so resistor 1/4W and a red LED? This will trickle charge the caps on the inverter, and all failure modes are accounted for:

 

- Short: LED is bright

- Resistor bypassed: LED fails open

 

If you're paranoid you can add a car fuse 5A or so.

 

Mind you for me 5V is the 'high voltage rail' so I may be missing something ????

 

[Crossy]

You need to consider the magnitude of the caps in the inverter and any startup leakage current that the electronics takes. A resistor small enough to charge things up in a reasonable time would send your LED into low earth orbit ???? 

 

I have 50 ohms and it takes several seconds for my LED (with 4k7 in series across the resistor) to go out when the pack is up near 55V.

[Pink7]

35 minutes ago, Crossy said:

OK. But please use Lucar or Faston connectors, don't solder to the switch.

 

 

You would use COM and NO for your pre-charge.

 

I was plan to solder, i need to solder on the terminal connectors on the battery cables also. Why not solder to the switch?

 

Pink

[Crossy]

1 minute ago, Pink7 said:

I was plan to solder, i need to solder on the terminal connectors on the battery cables also. Why not solder to the switch?

 

IF you are quick with a big iron, then OK.

Remember it's got plastic innards.

[Pink7]

13 minutes ago, Crossy said:

 

IF you are quick with a big iron, then OK.

Remember it's got plastic innards.

I did not think about that... Good Point Crossy!!

 

Pink

[Crossy]

6 minutes ago, Pink7 said:

I did not think about that... Good Point Crossy!!

 

I've been soldering since I was 10 or so plus spent 3 years as an apprentice honing my skills.

 

Even now I've occasionally melted something that really shouldn't have melted.

 

Modern plastics seem to be less resilient than they were when I was a lad...

 

Case in point XT90 battery connectors.

By the time you've heated everything up to solder the wires the ruddy pins are flapping about in the melted plastic.

[Pink7]

3 minutes ago, Crossy said:

 

I've been soldering since I was 10 or so plus spent 3 years as an apprentice honing my skills.

 

Even now I've occasionally melted something that really shouldn't have melted.

 

Modern plastics seem to be less resilient than they were when I was a lad...

I will check 2 mechanic friends  who live near me. They must have 4 of this connectors i guess.

 

Pink

[Pink7]

5 minutes ago, Crossy said:

 

I've been soldering since I was 10 or so plus spent 3 years as an apprentice honing my skills.

 

Even now I've occasionally melted something that really shouldn't have melted.

 

Modern plastics seem to be less resilient than they were when I was a lad...

 

Case in point XT90 battery connectors.

By the time you've heated everything up to solder the wires the ruddy pins are flapping about in the melted plastic.

I soldered quite a few XT60 ( Building and flying Rc Helicopters and Gliders) Still not happy with the outcome of the soldering..

 

Pink