UPS and heater(s)

I had another power outage last weekend (4+ hours), so I finally broke down
and bought a couple of refurbed UPSs. They should last a while as they are
36 amp hours each. The Goldfish tank only uses 24 watts (2 Fluval 304s), as
I won't connect the heater or lights. But I was wondering about the Tropical
tank, since batteries last exponentially longer under reduced load. Would I
not be better to have one 100 watt heater running twice as long, rather than
the normal two 100 watt heaters. In fact I was thinking about replacing the
two 100 watt heaters with a decent digital heater and leaving one of the 100
watt heaters in the tank as a backup. I would set the backup below the
threshold of the main heater (say 75°F) and connect it to the UPS. This way
the heater would not come on until the power had been off for a while.

Also do I need to connect the UGF filter to the UPS or can the bacteria
survive in the gravel for a while?

Bill Stock wrote:
I had another power outage last weekend (4+ hours), so I finally broke down
and bought a couple of refurbed UPSs. They should last a while as they are
36 amp hours each. The Goldfish tank only uses 24 watts (2 Fluval 304s), as
I won't connect the heater or lights. But I was wondering about the Tropical
tank, since batteries last exponentially longer under reduced load. Would I
not be better to have one 100 watt heater running twice as long, rather than
the normal two 100 watt heaters. In fact I was thinking about replacing the
two 100 watt heaters with a decent digital heater and leaving one of the 100
watt heaters in the tank as a backup. I would set the backup below the
threshold of the main heater (say 75?F) and connect it to the UPS. This way
the heater would not come on until the power had been off for a while.

100, 200, or 400W heaters will use the same amount of energy at the same
temperature, if they can maintain the temperature at all.
100 gallons of water maintains its temperature for a long while, and most
fish are fairly tolerant if it's once.
I would not have used UPSs, they arn't really the right tool, for small loads,
as the battery is sized to discharge through the inverter in some half an
hour, but the inverter will typically use 5%-10% of its nameplate power as
parasitic power.
So, with a 600W UPS, you may be looking at 80W draw from the battery,
rather than 30W, which you might get with a small inverter.

I'd have gone with a deep-discharge rated battery, and a small inverter,
combined with a small battery charger to keep it charged.

Not to say it won't work of course.
A tip, you may well find that you get better run-time if you daisychain the
UPSs, rather than having both powering seperate stuff.

Ian Stirling wrote:

100, 200, or 400W heaters will use the same amount of energy at the same
temperature, if they can maintain the temperature at all.

Well, it'll depend on the efficiency of the heaters. A more efficient
heater will use most of the electricity to heat the tank, whereas a less
efficient heater will use less of the electricity for heating the tank,
and the rest will be ... wasted ... as ... heat.

Hmmm.

Never mind then.

On Mon, 11 Jul 2005 15:31:58 -0500, Rocco Moretti
wrote:

Ian Stirling wrote:

100, 200, or 400W heaters will use the same amount of energy at the same
temperature, if they can maintain the temperature at all.

Well, it'll depend on the efficiency of the heaters. A more efficient
heater will use most of the electricity to heat the tank, whereas a less
efficient heater will use less of the electricity for heating the tank,
and the rest will be ... wasted ... as ... heat.

Hmmm.

Never mind then.



Well said.


--
Charles

Does not play well with others.

"Ian Stirling" wrote in message
...
Bill Stock wrote:
I had another power outage last weekend (4+ hours), so I finally broke
down
and bought a couple of refurbed UPSs. They should last a while as they
are
36 amp hours each. The Goldfish tank only uses 24 watts (2 Fluval 304s),
as
I won't connect the heater or lights. But I was wondering about the
Tropical
tank, since batteries last exponentially longer under reduced load. Would
I
not be better to have one 100 watt heater running twice as long, rather
than
the normal two 100 watt heaters. In fact I was thinking about replacing
the
two 100 watt heaters with a decent digital heater and leaving one of the
100
watt heaters in the tank as a backup. I would set the backup below the
threshold of the main heater (say 75?F) and connect it to the UPS. This
way
the heater would not come on until the power had been off for a while.

100, 200, or 400W heaters will use the same amount of energy at the same
temperature, if they can maintain the temperature at all.
100 gallons of water maintains its temperature for a long while, and most
fish are fairly tolerant if it's once.

Not arguing that 100 @ twice the time period is the same as 200 @ one time
unit. But if you look at the run time chart for most UPS you will see that
the last MUCH longer at smaller loads, i.e. not a linear increase. For
example my UPS lasts 8 minutes at 900 watts and 301 minutes at 50 watts. But
900/50*8 =144 NOT 301. I actually ran a test on the weekend @ 25 watts and I
got 8.5 hours out of the existing batteries, which are only holding about an
80% charge.

I would not have used UPSs, they arn't really the right tool, for small
loads,
as the battery is sized to discharge through the inverter in some half an
hour, but the inverter will typically use 5%-10% of its nameplate power as
parasitic power.
So, with a 600W UPS, you may be looking at 80W draw from the battery,
rather than 30W, which you might get with a small inverter.

I looked at the Inverter/Battery setup, but many of the inverters put out
POOR waveforms, which are detrimental to many powerheads. The UPS I bought
has a fairly good reputation for a 'cleaner' sinewave. Although I may still
go this route for powering up the fridge/freezer for longer blackouts.

I'd have gone with a deep-discharge rated battery, and a small inverter,
combined with a small battery charger to keep it charged.

Not to say it won't work of course.
A tip, you may well find that you get better run-time if you daisychain
the
UPSs, rather than having both powering seperate stuff.

Personally, I'd concentrate on keeping the UGF fed with oxygen as a priority
over the heating (unless you live in a very cold place). Oxygen starvation
in the gravel will quickly kill the bacteria in the filter. The last time I
lost power for a few hours, the temperature only dropped a few degrees but I
still lost a couple of fish a few days later.

Mark

wrote in message
...
Personally, I'd concentrate on keeping the UGF fed with oxygen as a
priority
over the heating (unless you live in a very cold place). Oxygen starvation
in the gravel will quickly kill the bacteria in the filter. The last time
I
lost power for a few hours, the temperature only dropped a few degrees but
I
still lost a couple of fish a few days later.

Mark

Thanks Mark the Powerheads on the UGF don't draw much current, so they I
have them on there now. The temp does get down to the low 50s during the
winter months, hence the concern about the heaters. I guess the tank should
hold it's temp for a while though, even at 50°F.

"Bill Stock" wrote in message
...
I looked at the Inverter/Battery setup, but many of the inverters put out
POOR waveforms, which are detrimental to many powerheads. The UPS
I bought has a fairly good reputation for a 'cleaner' sinewave. Although I
may still go this route for powering up the fridge/freezer for longer
blackouts.

I would not be concerned with sine/square wave...
I would check if this UPS can be used for the heater at all.
Most of UPSes I know do not let you turn on the device when on battery mode.
OR, they turn themselves off when detect a no load situation on battery
mode.
And this might be a problem because your heater will work in on/off mode...

I would avoid puting heaters/lights on backup power.
They are not needed in emergency situations.
Water circulation/gasses exchange is much more important.

"Bill Stock" wrote in message
...
Thanks Mark the Powerheads on the UGF don't draw much current, so they I
have them on there now. The temp does get down to the low 50s during the
winter months, hence the concern about the heaters. I guess the tank
should hold it's temp for a while though, even at 50°F.

My God!
Where do you keep your fish tank if you have the room temperature at 50F ?

"Pszemol" wrote in message
...
"Bill Stock" wrote in message
...
Thanks Mark the Powerheads on the UGF don't draw much current, so they I
have them on there now. The temp does get down to the low 50s during the
winter months, hence the concern about the heaters. I guess the tank
should hold it's temp for a while though, even at 50°F.

My God!
Where do you keep your fish tank if you have the room temperature at 50F ?

LOL, we keep the house at 60 at night, so the basement usually gets down to
55 or so, but can get lower on cool nights. It's cheaper to heat the fish.