That's a good starter idea to just check continuity on the coils sure. But often when a coil starts to fail, the very thin clear coat insulation on the wires start to break down and effectively this changes the number of coils from X to a fraction of X. When this happens, the INDUCTANCE changes on the transformer which is kinda like the coils resistance. And this change in coil counts will change the output voltage on the secondary coil. So checking the continuity is fine, but you should also check the actual inductance of the primary and secondary coils to see how degraded the transformer is. This is where it helps a little to use an analog multimeter instead of a digital. An analog will show the needle move as resistance is detected. In your video, this secondary coil was open meaning it probably burned through. It probably was pretty degraded before it burned through though and you may have been getting improper voltage on the secondary coil.
I just moved into a new home and want to instal an ecobee. I went to the transformer and only have 1 segmenet of 24v through the RED secondary, the GREEN secondary is grounded and doesnt have constant 24v. The GREEN wire is connected to my BLUE C wire. the result is that Im not getting constant power to my thermostat C wire. Is this a wiring problem?
When there's no connection the multimeter will display as "OL" which means open line or no number will be displayed on the multimeter screen. Which means there's a break in the transformer winding.
On the lower side with the 4 connection points, you'll notice on the schematic that there is a physical break dividing the 4 connectors into 2 pairs of 2. So, you should have continuity between a single pair, but not between both pairs, nor should you have continuity between the upper and any part of the lower half.
That's a good starter idea to just check continuity on the coils sure.
But often when a coil starts to fail, the very thin clear coat insulation on the wires start to break down and effectively this changes the number of coils from X to a fraction of X. When this happens, the INDUCTANCE changes on the transformer which is kinda like the coils resistance. And this change in coil counts will change the output voltage on the secondary coil.
So checking the continuity is fine, but you should also check the actual inductance of the primary and secondary coils to see how degraded the transformer is. This is where it helps a little to use an analog multimeter instead of a digital. An analog will show the needle move as resistance is detected.
In your video, this secondary coil was open meaning it probably burned through. It probably was pretty degraded before it burned through though and you may have been getting improper voltage on the secondary coil.
I just moved into a new home and want to instal an ecobee. I went to the transformer and only have 1 segmenet of 24v through the RED secondary, the GREEN secondary is grounded and doesnt have constant 24v. The GREEN wire is connected to my BLUE C wire. the result is that Im not getting constant power to my thermostat C wire. Is this a wiring problem?
I’m confused on how 160 ohms is a good electrical connection. Isn’t that extremely high ?
This is transformer. not resistor..
Transformer have lower ohm... Not same with resistor..
A transformer is an inductor so it will have a higher resistive value.
Not for some transformers
Would this be the same test for an audio transformer?
73 Paul AA1SU
Now do a vid on how to find data sheets on these chinese transformers with number that dont search. :P
Google the transformer name, number and schematic.
Whats your meter setting? Ohm 200? 2k? 20k? 2M? 😅 Wouldnt that be some handy info to give?
Doesn't matter for the readings he wanted to get
Thank you
Where do you set the meter
its on ohm's.
If a short circuit how we rectify that
Hi, can you explain how do you know the lower coil doesn’t have a connection please .
When there's no connection the multimeter will display as "OL" which means open line or no number will be displayed on the multimeter screen. Which means there's a break in the transformer winding.
On the lower side with the 4 connection points, you'll notice on the schematic that there is a physical break dividing the 4 connectors into 2 pairs of 2. So, you should have continuity between a single pair, but not between both pairs, nor should you have continuity between the upper and any part of the lower half.
ممنون از شما.
Sorry but everything was in shadow and I coi;dn't see any readings or anything. I will take your word for it.
Agreed
It’s great to have you cover the multimeter completely or forget to show us what setting you put it on. Wow
None these videos ever show the setting on the multi meter😂😂😂
Great Video