Help needed fitting Inverter, getting sparks

[Piston Broke]

Hi All,
Ive just fitted 2 brand new Varta 90amp batteries wired in parallel to our 2004 Burstner. I have a 120 watt solar panel through an EBL99 Elektroblok (off) and the LR1218 regulator. This has been covered and unplugged, but have tried fitting a Novopal 1500 pure sine Inverter. Connected positive cable with 120amp in line fuse to positive terminal on battery. But when I try to connect negative from Inverter to negative of the other battery I get sparks. Inverter is off and nothing connected to AC side.
Is it the Inverter or the battery wiring set up?
Scratching my head badly now ! Any help greatly appreciated

 

[Richard n Ann]

The inverter may have capacitors that will charge up when you connect it. If it doesn't blow the fuse I wouldn't worry about it, they'll only take a second to charge ?

 

[GPW]

All have caps on the input as stated, connect it up, then try disconnecting it for a second and reconnect and you should see no sparks the 2nd time as the caps will already match the battery voltage.

 

[Yorick]

What colour sparks ?

 

[Piston Broke]

Thanks for the above, gonna switch terminal first so connection is via screwdriver and not my fingers !!
And as for colour ....they're bright

^{_{Subscribers  do not see these advertisements}}

 

[Lenny HB]

Well I thought you were getting a "Sparks" to fit it for you.

That aside as you have fitted flooded cells I would change the LR1218 for a decent solar Regulator.

Piston Broke, that's the name of my Local.

 

[GPW]

If you are worried you can always use a 21W indicator bulb to connect it, if it's just a capacitor load it should initially light and then fade to a dull red glow.

 

[ambulancekidd]

Our inverter does the same thing & that's without turning the inverter on, apparently this is totally normal.
Just be very careful of sparks at a battery as the gases given off are highly flammable.

 

[DBK]

I wouldn't have the inverter permanently connected as it will continue to draw current when not in use. I fitted isolating switch, something like this will do:

 

[Piston Broke]

Thanks for all your replies, tried it again and still sparking, will have to work out how to test it as per GPW's comment.
Intend to fit RCD and remote switch on AC side , once I can get it connected safely

^{_{Subscribers  do not see these advertisements}}

 

[Reallyretired]

The on off switch on an inverter doesn't actually break the supply, as you will observe the switch is a titchy thing totally incapable of switching hundreds of amps. The inverter is thus effectively on when you connect it and quite a high current for a short time is normal hence the sparks. Remote switching if on/off should be to the switching circuit on the inverter. Just switching the output will not turn the inverter off.

 

[Piston Broke]

I didn't realise that, the remote switch that came with the Inverter plugs into an Ethernet type socket on the inverter which i thought would switch it off.
So if I fit an isolating switch on the positive cable from the battery, after the fuse and before the inverter, that should prevent the sparking on connection of the neutral. Ok that makes sense, thanks

 

[138go]

I used a 70 amp relay for ours as it's under a seat. Separate switch with small led turns relay on. You hear a bleep from the inverter when it turns on / off. No point in fitting RCD or a switch. The inverter will be consuming power even if you have the AC Switch off.