To Jonnymac
On the charging problem, I've found the problem, the resistor is damaged. Any ideas on repair/replacement? Could i re wind it with resistor wire?I have rewound a few of these resistors in the past and buy the wire from these people
https://wires.co.uk This is the wire that I used Bare Constantan.
50g 0.71mm Copper Nickel Wire
Ref: CN0710-050
Price: £5.44 Exc VAT (£6.53 Inc 20% VAT)
50 gram reel of 0.71mm 22 SWG Bare Copper Nickel Wire (Copper Nickel = Constantan = Eureka)
Data: approx: 1.24 ohms per metre, 50g = approx 14 metres
This was correct for the resistor that I needed yours will probably be different. What I did is count the number of turns. Measured the diameter of the resistor calculate the circumference the multiply that by the number of turns to give the length of the wire needed. In my case it worked out to 8 meters of wire needed for 115 turns to give me the 12 ohms required. Also you need to measure the diameter of the actual resistance wire.
Nickel Chrome resistance wire is also available but would have only filled about half the resistor. But It might have been used in your case. This why you need to do a bit of maths so you don't get the wrong wire.
50g 0.71mm Nickel Chrome Wire
Ref: NC0710-050
Price: £6.75 Exc VAT (£8.10 Inc 20% VAT)
0.710mm 22 SWG Bare Nickel Chrome Wire (also known as Nichrome Wire / Hot Wire Cutter / Foam Cutter / Heater Wire / Element Wire)
Data: approx 2.7 ohms per metre, 50 gram = approx 15 metre
Mick