W. H. Heydt
Posts: 12053
Joined: Fri Mar 09, 2012 7:36 pm
Location: Vallejo, CA (US)

Re: ARRGGH Power cuts.

Tue Aug 23, 2016 3:30 pm

MarkDH102 wrote:I've been using the RavPower mentioned above in situ for 4 weeks now.
I've had a few short power cuts in that time and have pulled the mains adapter out occasionally with no problems.
I'm drawing about 230mA fairly constantly.
When we get a power cut, Western Power toggles the power a few times in a minute (I guess it comes on then cuts due to trip at the substation) before we get a stable power back and I'm surviving that.
One thing I don't know is how much energy the RavPower is able to store after a month in this configuration but when the power cuts, all 4 led's stay lit indicating a fully charged power bank.
That's pretty typical of a utility power failure. The system tends to "bounce" a few times while trying to pick up the load. The "bounces" are moderately likely to contain voltage spikes, especially if your circuit branch contains large inductive loads. Hence, my preference to always start with a surge protector. Let the cheap component fail first, while it protects more sensitive, more expensive, or harder to replace equipment behind it, even if that equipment also contains surge suppression circuits.

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johnb_summers
Posts: 285
Joined: Thu Aug 04, 2016 7:48 pm
Location: Bushey UK

Re: ARRGGH Power cuts.

Tue Aug 23, 2016 4:38 pm

I Have a PowerWalker VI 650 IEC UPS 650VA 650VA/360W, this powers 3 raspberry pi's, one Linux server, one Synology server and the router and the land line phone, with all on it uses just 19% that the powerwalker can supply, you can buy them for under £100 in amazon, I have had a few power cuts and they have had no affect as the powerwalker works perfectly, the only annoying bit is the bleeper but I am sure that can be adjusted if I looked, it really is plug and play, just take it out the box, plug it into the mains then plug everything you wanted protected into it.
MyPi Developer
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JimmyN
Posts: 1109
Joined: Wed Mar 18, 2015 7:05 pm
Location: Virginia, USA

Re: ARRGGH Power cuts.

Tue Aug 23, 2016 8:19 pm

W. H. Heydt wrote: That's pretty typical of a utility power failure. The system tends to "bounce" a few times while trying to pick up the load.
That's due to the "reclosers" used on high voltage substation distribution. When a line shorts out it trips the breaker, it then waits a set number of seconds and it closes the breaker again automatically. Since it's high voltage (4K or more) it will frequently blow the tree limb or broken dangling wire away and clear itself. So reclosers will usually try three times to clear the line before it gives up and remains tripped. That's why line crews notify the substation when they are working on a line and the reclosers are then turned off. If the crew accidentally shorts something the breaker won't keep closing to try to clear the short by brute force.

MarkDH102
Posts: 394
Joined: Fri Feb 13, 2015 3:18 pm

Re: ARRGGH Power cuts.

Wed Nov 23, 2016 11:24 am

Another update. The RavPower is still running strong.
It had its first big test the weekend. A 7 hour power cut.
No problems at all.
I think the RavPower's are on offer at Amazon (UK) at the moment too...

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