I currently have a Hub 4 router, made by Arris. Would like to add battery backup in case of power outage. DC plug is unusual size, external diameter 6.0 mm. Unable to measure internal diameter. What type of DC plug is this? Where can I buy suitable battery backup?
Usually folks focus on a mains APC UPS or similar then the Hub's factory PSU can be used.
A mains UPS may also power your laptop or PC for a while too & if you are in an RFoG street like us, the ONT needs to be powered as well.
The real question is are the street cabinets in your locality protected by UPS, because if they are not, I fear installing a home UPS may all be for nought.
There are battery products on the market that can be inserted between the manufacturer's 12v supply and the hub/router. This maintains smooth current in the event of grid interruption, subject to finding the correct plugs. A UPS contains an inverter and changeover relay. Hence difference in cost & complexity.
I accept the point about power continuity in street cabinets.
This eBay listing (if it is to be believed) quotes plug spec's in the written description part way down
https://www.ebay.co.uk/itm/144655379363
But note the current carrying capacity requirements of barrel plugs in this past topic
Hub 5 dc barrel plug specs | Virgin Media Community - 5535594
As per Client62 though, your battery backup won't be much use for maintaining an internet connection if some other part of the VM network goes off in a power cut.
You would need to find out (not easy) if your street cabinet amplifier is powered from a different local transformer to the one your house supply is fed from. If the two are on the same, as mine & many others are, you are wasting time & money buying a chocolate tea pot. There are no UPS units on VMs HFC networks, so if the public electricity supply fails all the coax sections in that area will also go down, whether you have backup power indoors or not.
VM has a battery backup unit (BBU) in its power cabinets which is typically sized to provide enough DC power to keep optical node cabinets, line amplifiers, MSAN cabinets and VHUBs running for a limited period for perhaps 1-2 hours at most. As most power outages are uncommon and last for just a short time, I think battery backup for most users is a waste of money.
If you are supplied directly from a node cabinet you would be fine. Between me and the node cabinet are a further 3 cabinets that take power directly from the local grid. The last one of those is on the same transformer as my house. My neighbour (who is also a VM customer) bought a UPS home from work to act as a backup, but no longer uses it as the entire service in five postcodes around us goes down when the local transformer goes out. We also get outages if either of the other 2 cabinets mentioned are affected.
Consider a Plan B that involves powering your work laptop and using your work mobile with a USB cable as the internet connection. This way is more stable and the mobile charges.
But give a thought to all the other practicalities.
A power cut today at 10am in August leaves us with many hours of day light, but what if the outage occurs late afternoon / early evening in winter, before 4pm you would need to have room lighting on a UPS too.
