26

As indicated by Ecnerwal the picture you show is an old style telephone line hookup. When you go looking around for your doorbell transformer it may look like one of these: Mounted on cover of an electrical junction box similar to the following. Liable to be found in garage or basement fairly close in distance to the bell button and bell unit. Picture ...


18

Nope. That's a phone line terminal block. Old school. May have rudimentary surge supression built in. The heavy black wire is drop cable (from the pole to your house) It's not your doorbell transformer.


14

Transformer. Probably for doorbell, possibly for hard-wired controls for garage door opener. The "string" is fabric-insulated low-voltage wire, which was commonly used for that purpose.


13

The answer is NO. All wired doorbells must be low voltage by NEC. You can find chimes with the transformer in the chime box, or mounted in a jbox behind the chime box, and you run 120 vac to the transformer, but all the actual chime and buttons must be wired from the low voltage side of the transformer. It's a simple series circuit.


12

The bigger problem is the transformer is going to set you back about $100, so it spectacularly fails to make sense for a $40 humidifier. Dollar for dollar, if you're coming to North America, you may be better off just adding a couple 240V circuits to your house, and running the appliances off 240V straight shot. North America has both 120V and 240V ...


8

Do not replace the junction box. It is a standard junction box and there is nothing wrong with it. Backstab connections fail more often than transformers Look at the receptacle. See how the wires are connected? They're "back wired" with a backstab style connection. That is only allowed for 14 AWG solid wire, the receptacle's labeling plainly says ...


8

The worst hazard here is snagging your clothes. The transformer is low-voltage, so you can touch the wires and probably not feel anything. If your hand was wet, you might get a buzz, but it's not dangerous. Some transformers can get warm, but doorbell transformers normally do not because they are very low power devices. You could hang a shoebox on it or ...


8

Something like a dehumidifier which has a fairly high load and a high start up current, will require a larger transformer. Cost and portability will be major considerations. Smaller appliances with low current draws, will be easier to fit to a small transformer. For reasonable quality transformers, figure a loss of about 3%.


7

That's telephone. It's not a transformer. It's a terminal block. Call up the phone company and ask them to have someone come out and show you where your point of demarcation is. That's where the wires stop being their responsibility and start being your responsibility (unless you have an in-house service plan as part of your bill). It looks like an ...


5

In the UK, the vast majority of doorbells are battery-powered. On my old-school mechanical doorbell, two alkaline D-cells are lasting me around 3 years. As for why there's an external transformer, that's simple. It's not "antiquated", it's actually a modern phenomenon. All mains-connected equipment needs safety testing (CE, TUV, or whatever your local ...


4

This is a common way to install a 24V low-voltage transformer. These are used for HVAC thermostats, doorbells, garage door opener controls, and other "control" applications. (For instance, if you're hooking up a Nest thermostat and looking for the "C" wire, it's one of those. The other is the "R".) Here, the transformer is part of a junction box cover ...


4

This is where the low voltage and high voltage sections of the UL code interact in an odd and problematic (for you) way. The wire from the chime to the button is low voltage. You also want the chime itself to be powered directly from high voltage. The two voltages cannot be placed in one junction box. So your desired doorbell chime unit must support ...


4

Um, I don't know where you got the term "power stealing". What you describe as that, is exactly the normal way to do that thing, and the right way... unless you are aware of some capacity issue on the transformer (as is sometimes seen in transformer-relay combos). As far as the R and C terminals, any HVAC transformer has two pins on the 24V side... They ...


4

The lifetime of an autotransformer is indefinite, and does not necessarily end with a short circuit. Barring a transient on the mains, water leak or some other external event, there is no reason it should fail. However, if the low-voltage part of the winding were to open (as well as if the high side were to short), you'd also be faced with full line voltage ...


4

Anything is possible, but my bet is on a thermostat transformer. Typical (US) thermostats run on 24V AC. Typical doorbells (though there seems to be less consistency than with thermostats) use 16V AC. Get a multimeter. Test the voltage: 24V - Thermostat 16V - Doorbell Something else? Post it here and we can try and figure it out.


4

Because you have too much lighting load for the power supply (not transformer*) to cope with, so it is crowbar-ing. Reduce load. This is a good time to think LED. * "Transformer" is a proper term for a very specific thing, which this is not. Transformers are quite heavy and withstand short-term overload very well. This weighs 6.4 oz. for 150W, and ...


4

Adding transformers will not "stabilize" anything, I have no idea where you got that idea, but it's wrong. Sometimes people step up the voltage to a higher level (like 480V) and back down again for a long distance run so that the current is less, because less current results in less voltage drop since voltage drop is a function of I (current) Squared / R (...


4

Straight up You cannot afford to fall below 110V. Ok. Supply at your house is supposed to be 120V so we have a little room to play with. If you use 8 AWG cable, voltage drop will be limited to 8.29V on a full 20A load, giving 111.71V. That meets your criteria. If actual pulled amperage is less, voltage drop will be proportionately less, and ...


4

The old transformer has identical wire colors for hot and neutral. The new one differentiates them. To connect the new transformer, connect the black wire from the new one to the same black wire where your old transformer was connected with the wire nut. Connect both the green and white wires to the same spot where the black and green are connected together ...


4

You're wasting about 2-3% of the transformer rating in inefficiency. If you're switching secondary voltage, then you're paying for the primary winding losses 24 hours a day even if there's no load on the transformer. The transformer is just one more item that can fail and leave you without your appliances.


4

Is the actual problem "I need to power a bunch of 120V devices" or is it "I have a bunch of gadgets that need correct power" ? There is quite a difference. In the picture, it looks like a power adapter (a.k.a. "wall wart") is plugged in. Many wall warts (or other types of adapters, like "laptop bricks") can actually ...


3

No matter what you do, yes, you have to follow electrical codes (in North America, the NEC), and this means proper enclosures for any mains voltage stuff. The NEC doesn't have anything to say about low voltage (<= 30V) wiring. Essentially this comes down to preference, there's no right answer as to what is 'better'. A hard-wired solution can have a ...


3

Here is how manufacturers make an appliance one voltage or another. electronic switch-mode power supply. These can input a huge range of voltage, for instance many fluorescent ballasts take 90-306V. If you see that, don't be surprised, it really works. The machine runs on low-voltage AC or DC from a pluggable "wall wart" transformer, and they simply ...


3

You're not measuring the amperage, you are measuring the voltage. Set it to measure DC Volts on the 20 scale, read. The maximum voltage for the meter is printed right on it, 600. The device you have is not a transformer, it is a DC power supply. When you connect your lights, measure the voltage again with the lights connected. Don't try to measure the ...


3

I can only answer this question as if I were a contractor. In general we order the drivers and material approved by the manufacturer. Meaning I would stay with the original equipment. If you choose not to use there approved equipment then it might cause damage to the entire system and void any warranty you may have for replacement. As a contractor I would ...


3

In my freshly renovated kitchen I have a bunch of FÖRBÄTTRA 60cm LED light panels paired with an ANSLUTA 30W transformer and daisy chained 10W transformer (more 24V outputs) controlled by a 2.4GHz remote. I can confirm the voltage levels at 0%, 50% and 100% brightness are 2.2V, 22V and 24V. I was surprised to find that a 0% brightness (off) the panels were ...


3

I have run multiple thermostats and even a 24v damper off a single transformer. Most thermostats are very low draw but to make sure look up the power requirements for each and add them together. Now compare that to the transformer wattage/ amperage. If less is needed from the 2 stats than the transformers rated output you are good to go. If the same or more ...


3

1 - Figure out what fuse/breaker controls that set of outlets and turn it off. That is always the official advice before removing an outlet cover, but especially important here as you don't know what you will find. 2 - Remove the outlet cover. If the wires go out of the junction box separately from the regular AC power cable then you should be able to ...


3

Yes, for a short time, and then there will be a BANG and a fire will start. Whether that happens in 5 minutes or 5 days is based on the quality of the build of the equipment. Siemens >> random junk off Alibaba. If you plan to do that, then buy a 240/480 autotransformer in the first place, which can also be used for 120/240 at half the VA. This type is ...


3

The burning smell is the insulation of the winding conductors burning and is generally indicative of irreparable damage. It may still function, for a while, but has been severely compromised. Further failure often results in flames...


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