Fridge probes and the difference

[markymark2406]

In my job I have been tasked with the maintenance of small clinical fridges (controls only Not gas) and most of the fridges are the LEC type with LAE controls (as pictured) I like to know more and the types of thermostat probes which are used, I have tried some which are not comparable with the controller mentioned, I know this by when you get a temp reading of 100 it some random figure when the incorrect probe is wired in,
Any Education appreciated

 

[Nozzle]

https://www.omega.co.uk/techref/colorcodes.html

This any help for ya? I've made the assumption that the red and white wires are going in to terminals 10 and 11 and therefore are indicators of the thermocouple type.

Or it could be a thermistor.

Where does the blue wire go?

Nozzle

 

[ericmark]

The STC-1000 has been the unit used for years by home brewers and amphibian keepers, there are really designed for fridges and freezers, but are as cheap as chips, the Inkbird 308 has replaced it in the main as it comes ready wired, but it would seem they would do for what you want. Also some called ITC-1000 and one I have MH1210A which was slightly cheaper, google and see what you think.

 

[jj4091]

You could ask here https://www.hawco.co.uk/en/refrigeration/controllers/lae

 

[Phil-De-Fridge]

Looks like the LAE 153s were fitted with an NTC 10K resistance probe, you could confirm this by using the table for this resistor/temperature probe as below:

The probe fitted to this controller is the 10k NTC type (LAE SN4K15P1, Part number 00-556187) with red letter identification. LAE NTC10K Temperature Resistance Table
Temperature
(°C) R-mid (KΩ)
-25_______87.559
-20_______68.237
-15_______53.65
-10_______42.506
-5________33.892
0_________27.219
5_________21.63
10________17.926
15________14.674
20________12.081
25________10
30________8.315

Sorry for the formatting, but hopefully you should be able to see what this is about.

Easiest way to check a temperature reading/resistance for a probe designed for fridge use, is to use Ice and water (let the ice settle/melt; but not completely melt) and check the resistance for 0°C 27.217 KΩ

Kind regards

Phil