UPS solution for ONT and SH2

[WSH]

As people have pointed out, their use in industry is usually just for a few minutes to do a controlled shutdown or bridge the gap until the generator kicks-in.

The conversion back to AC is still quite inefficient and so the Ah of the battery on its own is not a good guide.  The discharge rate is also non-linear.  Your best bet is to download the UPS manufacturer’s spec’s and look at the graph of the discharge curve they provide.

[philip42h]

I'm pretty sure that there is no 'official ruling from BT' on what accessories are available once full fibre is installed. It used to be two of these or one of those but I believe that 'stopped' and it's now up to whoever you speak to on the 'phone as to what you get for free.

No battery backup was offered for free - I bought both units at about £85 each. At the end of the day the cost was worth it for peace of mind. The units were described as:

• Battery Back-up for BT Digital Voice service (Non FTTP)
• Battery Back-up for BT Digital Voice service (FTTP)

IIRC the FTTP one powers the ONT; the Non FTTP one powers the SH2. 

(The BT Shop is back but is now an EE shop!)

[oldbuffer1]

That's what I suspected - everything is negotiable except if you call first thing on a Monday morning! 

I think I will be getting the BBU that keeps my DV alive  ie the one that powers the SH2.  (I might try a splitter cable to see if it will power both SH2 and ONT, at twice the discharge rate no doubt)  Failing that, the Eaton I have on order should do for the ONT which is now a miniscule device compared to previous versions.

Whatever happened to good old fashioned POTS?

PT.

[philip42h]

If you look back through my earlier posts ...

The BT supplied CyberPower units are rated at 24W, the ONT is rated at 12W and the SH2 is rated at 18W - so, on paper, you'd be trying to draw 30W from a 24W supply if you added a splitter to a single unit.

In practice, who knows ... 🙂

[WSH]

No, as I said, it’s a non-linear curve.  The assumption that twice the load is half the time doesn’t work except at very small loads.

Another point I forgot to mention is that age of the battery is also a big factor.  Even a battery that’s only two years old can last for far less time than it did when it was new.  They deteriorate quite quickly sitting on standby.

[oldbuffer1]

Well well! Parcelforce just delivered a bunch of handsets plus 2 x Cyberpower BBUs! So I guess I wont be trying to drive the ONT and the SH2 from one unit. Unfortunately as they are each the size of a housebrick and the ONT/SH2 combo is in the porch, I don't think the O/H will appreciate having to look at them every time she goes out. Will definitely have to box the whole lot in (with plenty of airspace for heat dissipation).

PT

[gg30340]

Why don't you keep them in a cupboard and charge them up once a week and only plug them in and use them when you have a power cut.

[oldbuffer1]

Good idea. However, power cuts here are few and far between plus being relatively short-lived. By the time I've remembered where I put them and plugged them back in, the power would be back on again. Must try and justify their use somehow.....

[Matt-Sussex]

Your Post really helped, I am now all set up. However I still have a small problem.

I wish to position the BT Smart Hub2 further away from the CyberPower Battery Back-up unit ( DTB24U12V-BT1) and require a longer Hub Connector power cable or Extension Cable of about 3 meters. I am not sure of the cable specification, it may be  something like- 12Volt DC 1.5A/2.0A with maximum current draw of 30 Watts, I don't know the size of the Pin/Tip.

Can anyone advise me of the correct specification?

Matt

[WSH]

The plug on the SH2 power connector is 3.0 x 5.5 mm and 11 mm long.  I know as I’ve tried to do the same thing.

Good luck finding an extension lead.  BT have used the most obscure DC plug known to mankind.  The old Home Hub 5A was the same, although the 5B was a more standard size.

The only supplier I could find of that size was in the US and they only made the plugs not the sockets.  If you find anyone that does do solder plugs and sockets in this size I’d appreciate you posting it here.