Power variations when using cooling mod.

[bomberbaz]

Hello all.

I am having a variation in my voltage which I am not sure if it sho9uld be a concern or not.

First my rig. It is an AZ GTi in EQ mode, a ZWO ASIAir plus, a ZWO 183 mc main and ZWO 224mc guide. The whole lot is powered by the battery from a SW 17ah powerbank.

To the ZWO 183 I have attached an homemade peltier cooling mod which draws 27W. (2.2a)

When the rig is powered up without the cooling mod, power draw is stated at 0.4a - 5.5w - 12.3v

When I switch on the cooling mod this goes to 2.6a - 27w - 10.4v

Two queries regarding this. First the reduced voltage, will this cause any harm to the parts as described above?

Will it shorten the battery run time and cause things to start to go awry.

Am I better considering other methods of powering my imaging rig.

[tomato]

I have two cameras retro fitted with Peltier coolers, with the whole set up powered from a mains powered 12V power supply. The on rig voltage runs at 12.8v but drops to 12.0v when both coolers kick in.

I think you are in risky territory if your supply voltage is down at 10.4v when the cooler is running.

[ONIKKINEN]

Damaging? Probably not, but your gear may not work properly.

I am amazed you have not run into mount tracking issues with this setup. 10.4v is definitely not enough to run any 12v motors at their intended powers. 12v appliances run best at 13-14 volts.

"Dumb" batteries like the skywatcher one are terrible for anything but very low power consumption gear just because of what you experienced, they are imcapable of producing steady power under load (especially if its cold).

Smarter, regulated power supplies keep the output voltage high and adapt to power draw. I have this one: https://eu.ecoflow.com/products/river-portable-power-station?variant=37254607863972

(€€€,i know....). 

It supplies 13,6v until the last drop of power has been drained.

I would look at a regulated power supply, or wall power if thats possible. No way you wont run into trouble with your current battery!

[bomberbaz]

I decided to stick with a provider I know andd trust, FLO in this instance and got one of these

Celestron Lithium 13.2 Ah LiFePO4 Powertank Pro | First Light Optics

According to some research I found which was a comparison between lead and L-ion batteries these seem to pump out a steady 12v all the way down to circa 80% drain, plus are good for a quoted 2000 charges. If the latter is the case it will probably outlast me.  

[bomberbaz]

heads up on this. Now using a celestron powertank lithium pro. From the socket it claims 12v / 10a so should be smashing it. 

I am still getting a drop in voltage when using the whole setup. Power draw according to the air+ is 2.7a and Voltage now at 10.7.

Can any of you ZWO ASI Air plus users with cooling who are using the Air+ look at what their own voltage runs at when cameras, cooling, dew tapes etc are all switched on please.

cheers

steve