Selecting the correct adapter for my Amprobe TMD56 data-logging thermometer

[Teemosan]

Hi all,

I'm new to the site.

I just bought an Amprobe TMD56 data-logging thermometer. This device here:

http://www.amprobe.com/amprobe/usen/hvac-tools/thermocouple-thermometers/amp-tmd-56.htm?pid=73414

It takes 4 AAA batteries, but has an optional DC adapter input. In the manual it lists the adapter specs as:
DC IN: 12Vdc, 150mA,

It's positive (internal) polarity, jack size 3.5mm x 1.35mm

I guess I don't understand this correctly, because I thought if the device ran on 4 x 1.5v AAA's it would require a 6V adapter. For amps I'm guessing it'll only draw what it needs so if I get an adapter that's = or > 150mA it would be OK. Is that correct?

So first I need to clear up my misunderstanding of the difference between the devices battery operated voltage and the adapter voltage. Or is there even a difference?

Then I need to get a correct adapter. I see a lot of these multi adapters on Amazon, eBay, etc - devices like this:

https://www.amazon.ca/IKOCO-Universal-Regulated-Replacement-Electronics/dp/B01JFZ8BO2/ref=sr_1_48?ie=UTF8&qid=1493597032&sr=8-48&keywords=12v+adapter

Would something like that work?

Thanks
   

[Paul Price]

The output voltage is stepped-down in the instrument to a  regulated voltage near the battery voltage and that is why it is 12V, which is a convenient off-the-shelf and popular spec.  which also possibly lowers cost. You could use probably any regulated 12V adaptor you can find that matches the connector and has >150mA output on your instrument since the power requirements are very low and almost any 12V wall-wart or brick regulated 12V power supply is rated >150ma.

[Teemosan]

Paul, thanks, I appreciate you taking the time to answer, and the explanation. Easier than I thought  I'll get one based off that info.
thx,
Tim

Edit: Also, being new to the forum, I can't see a way to select best answer or mark as solved. How do I do that, or do the mods close out the threads?