battery backup

I've had solar PV on my roof for 6 years now; very pleased with it, but had to repair it last week by replacing one of the 16 micro-inverters, one under each solar panel. I had bought 2 of these as spares and, after having the defective inverter replaced, now have 2 spare again. This got me...

Some may know that I have a APC Smart 1500VA UPS that protects my network and rack server at my home. It is normally at a 25% load. The UPS was original manufactured in September 2007 and I bought it second hand on ebay in 2013. I have replaced the batteries twice since having it and are due to...

Just wondering what BS7671 says about fixed sockets being RCD protected when being fed from a portable UPS (i.e. removable rack type UPS) when the the UPS is operating on battery mode and the Line & Neutral conductors are isolated from Earth. (Effectively a Isolated Terra based earthing system.)...

How do you do this? Does it require any additional kit like a charger /dummy load? Surely it's can't be as simple as just measuring the voltage, as the health of a lead acid battery is determined by it's storage capacity and not it's terminal voltage. The Yuasa test method seems to require...

I need to replace the backup battery for a Guardtec 595 house alarm but can't find anywhere which one I need. Also any idea where I can get one ASAP from? Many thanks in advance

I need to get two new 7ah 12V Lead Acid batteries for my 1000va Belkin UPS as they are shot after 3.5 years of use. They clearly need replacing as the UPS just shuts of immediately on power loss and the batteries are very hot and slightly swollen out. Ones even resting around 6V. They are...

Hi all, I'm currently in the process of building a ups to back up a cctv system. I have been using this as a guide http://www.instructables.com/id/Super-Simple-Super-Cheap-DIY-UPSCCTV-system-fro/ I've got as far as the relay and I'm now stuck as this guide does not explain it very well (not at...