Portable 9v Supply for a data logger

Calahonda52

need to set up a temperature/CO2/humidity data logger that needs 9V DC and there is no power supply in the location for the 230V to 9v DC 1.3A trafo.

the data logger has 6 by 1.5 v batteries for clock time storage

I have no idea what the logger will draw so would a few rechargeable 9V (PP3) in // do or perhaps a 9V battery form a cordless drill?

Does not need to be elegant!

An hour of readings per day will do me

Thanks as always.

Andrea B.

Calahonda52 wrote: »

need to set up a temperature/CO2/humidity data logger that needs 9V DC and there is no power supply in the location for the 230V to 9v DC 1.3A trafo.

the data logger has 6 by 1.5 v batteries for clock time storage

I have no idea what the logger will draw so would a few rechargeable 9V (PP3) in // do or perhaps a 9V battery form a cordless drill?

Does not need to be elegant!

An hour of readings per day will do me

Thanks as always.

I see by google that units out there at 1min logging claim to run a month on a 9v battery.
Very hard though to compare without you giving a spec.
Aside, why not try a few days dummy run on a 9v battery?
For comfort then put a few in parellel.
Are you comfortable doing this and identifying correct polarity on input?
Is your power supply on a plug in jack or direct wired?

Calahonda52

Andrea B. wrote: »

I see by google that units out there at 1min logging claim to run a month on a 9v battery.
Very hard though to compare without you giving a spec.
Aside, why not try a few days dummy run on a 9v battery?
For comfort then put a few in parellel.
Are you comfortable doing this and identifying correct polarity on input?
Is your power supply on a plug in jack or direct wired?

Thanks,
Having fried a pcb in a video camera 20 years ago I learned all about different voltages from plug-in trafos and polarity:)

Am happy I can wire it correctly, good idea re the test.
I think the CO2 bit consumes a bit of juice and the screen stays on as well....

drill(14.4v) /car battery anna dc converter

Calahonda52

Thanks was hoping for something less bulky, there is already enough kit in the bag without a big truck battery!! just kidding re battery, bag is heavy enough

Well you have to measure the expected load to spec the right sized battery.
If you over-discharge them modren li-ion batteries by hot wiring them you can brick the driver circuit boards and they won't take a charge. Elf and safety nanny state malarkey..ni-cads will work fine.
That dc converter is mostly plastic and air too, the circuit-board has an envelope the size of half a credit card.

Calahonda52

Thanks, I have asked the maker for the steady state amp load that it draws

They usually just regurgitate the datasheet.
Run it on the mains supply and stick a DMM ammeter between the PSU and load. Multiply this by runtime = amp hours. +5% DC converter losses, +20% safety margin, +10% NiCad / +40% Li Ion / +50% Lead Acid

If you want to get real fancy use the min max average meter feature for intermittent duty loads.

Calahonda52

From the makers:
The logger AC Input Power consumption is 165mA..., so no need to drive my EV into the meeting room!

Clicky

Calahonda52

Thanks, I presume I need to supply the 15V DC input for charging?