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Internet # 340751748

Model # 3040TR

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Dual-Volt (16V/30VA or 24V/40VA) Wired Doorbell Transformer-Indoor Low-Voltage Power Supply for Smart Doorbells

$20.97
  • Dual-Volt (16 v/30 va or 24 v/40 va) wired doorbell transformer
  • Supports modern doorbells that require additional power
  • Ul-listed safety certification for reliable indoor use
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Product Details

About This Product

Upgrade or replace your doorbell power source with this Dual-Volt (16 V/30 VA or 24 V/40 VA) Wired Doorbell Transformer, designed to deliver consistent low-voltage power for smart video doorbells and traditional wired chimes. With a higher 30 VA or 40 VA capacity, this transformer supports modern doorbells that require additional power for video, motion detection, and Wi-Fi connectivity. The transformer installs easily outside a standard metal electrical box and features UL-listed safety certification for reliable indoor use. It has a durable metal housing that helps ensure long-lasting performance. Ideal for new installations or replacements in residential settings.

Highlights

  • 16 Volt/30 VA or 24 V/40 VA output (cannot use both Voltages at the same time) provides reliable power for smart video doorbells
  • Compatible with ring, nest, wyze, eufy, arlo, and most wired doorbells
  • Ul listed for safety and indoor residential use
  • Hardwired installation fits outside of standard metal electrical boxes (do not install the transformer inside a wall because the transformer generates heat and needs space and proper ventilation for heat dissipation)
  • Heavy-duty metal enclosure for durability
  • Ideal replacement for older or underpowered doorbell transformers
  • Please note: it is not recommended to use a 24-Volt transformer with a 16-Volt chime as the doorbell and/or chime can wear out, chime model chm24-Volt is compatible with a 24-Volt transformer
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Product Information

Internet # 340751748

Model # 3040TR

Additional Resources

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From the Manufacturer

Specifications

Details

Color Family

Gray

Returnable

90-Day

Voltage

16 volt, 24 volt

Warranty / Certifications

Manufacturer Warranty

2 year limited warranty

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Customer Reviews

4.9 out of 5

  • 4.9 out of 12 reviews
  • 100% recommend this product
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Showing 1-10 of 12 reviews
Beast of transformer for the modern devices
Wow this is a beast of a transformer! This guy is heavy due to the high power output. I'm using this to replace my 40 year old unit that has powered my door bell, lighted street number sign, and old simple thermostat for the last 40 years. With this beast of transformer I can now also power a modern smart wifi enabled thermostat. Because this transformer is a beast, I did have to upgrade my electric outlet box since this guy is massive. Also, the 1/2 inch threaded nipple is plastic and not metal, so i hope there will be no cracking another 40 years down the road.
by
  • Recommended
Simple multi volted doorbell transformer came in handy
There really isn't alot to say about a wired doorbell transformer other than it works. I have two of these in the home when I bought my house. However, we installed door bell cameras. When someone rings the new camera door bells there is a soft sound that is created from the doorbell but it is mostly outside. I needed a way to hookup the existing door bell to my cameras. I also built a new entrance way and wanted a door bell camera there as well. I am using this device to create another low voltage connection where we did not have one previously.
by
  • Recommended
Excellent upgrade for underpowered transformer replacement and running multiple doorbells.
I selected and installed this product since I had been wanting to add a second video doorbell camera at the back door of the home for some time now, but didn’t have a transformer that supplied enough power for two. This unit is simple to install and would be a great upgrade to replace an old weak transformer or for running multiple video doorbell camera systems. For single use, the 16V/30VA terminals are plenty. If running two video doorbells like I am now, it’s no issue to up the output and use the 24V/40VA terminals. It definitely has the power to run multiple doorbell cams. I measured output with a Fluke multimeter and was getting 25V to 27V at the back door. Unit appears solid and well made and includes a 1-year warranty, but if the product is registered with the manufacturer they will give you a second year of warranty coverage as an upgrade free. To me this is a great bonus feature.
by
  • Recommended
1 found this review helpful
Great upgrade
Hey guys and girls so this is the transformer for a door bell it reduces the line voltage of 110v/120v to a usable voltage for the doorbell button and chime, I've installed a few of these in my time very easy to install, basically you mount it to a steel box the steel box can be remote or directly connected to the panel, then run the low voltage wires from the transformer to the doorbell button, really easy, I prefer the transformer over a doorbell that uses batteries
by
  • Recommended
Ring ring
This doorbell transformer is exactly what you need if you have a smart camera doorbell. The last transformer I had created a delay, but this one makes it more much faster. No more delay from when my houseguest presses the ring bell button to when the doorbell sound rings. It’s amazing to think that I waited so long to get this. The device works amazing!
by
  • Recommended
Dual-Volt (16V/30VA or 24V/40VA) Wired Doorbell Transformer-Indoor Low-Voltage Power Supply for Smart Doorbells
The Newhouse Hardware Model 3040TR, is a Dual Voltage Wired Doorbell Transformer, that operates from 120V AC Hardwired power and is Designed to Produce higher 30 VA or 40 VA capacity, at either 16 Volt/30 VA or 24 V/40 VA output that provides reliable power that modern smart video doorbells require. It has UL-listed safety certification, It is 2.5 H x 2.5 W, and easily Connects to a standard metal electrical box with the Threaded Connection. This Product is Well Made Easily Replaced my original under-powered Transformer. I find it to be Very Dependable. Excellent Instructions are Provided. I am Glad to have it to update my home.
by
  • Recommended
I like that the 110 lead wires have ample length and the leads have finish ends for quick and easy connections
I chose the Dual-Voltage low-voltage wired doorbell transformer for Smart Doorbells simple started the one in our recently purchased home does not work. I like that it even comes with the retaining nut to tighten it to an electrical box. I like that it can accommodate most Smart doorbells by the way you wire the low voltage wires. I like that the 110 lead wires have ample length and the leads have finish ends for quick and easy connections.
by
  • Recommended
Supplies increased power necessary for replacement smart doorbell/chime
We decided to replace our front door builder supplied wired doorbell and chime with a smart video doorbell and a louder chime. Increased power was needed and this transformer was an easy installation by just attaching it to the wall next to the previous transformer and attaching the existing wires. Dual voltages, (either 16V/30VA or 24V/40VA), are available just by selecting the appropriate connections on the transformer. No metal housing is needed and instructions specifically state it should not be enclosed in a housing because of generated heat. We installed a Ring doorbell but this is compatible with almost all brands of smart doorbells and UL certified'
by
  • Recommended
Easy replacement
My home had the older transformer that powered my door bell and lighted up the outdoor push button. When I replaced the outdoor push button with a video camera, my video door bell would not function at times and I had to trip my circuit breaker. I connect only the 16V30VA when I replace my doorbell/video power source with this wired doorbell transformer. It works so far, so good.
by
  • Recommended
Works great, easy to install and figure out.
by
  • Verified Purchase
Showing 1-10 of 12 reviews

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Product Snapshot

Ideal for upgrading smart doorbells, ensuring consistent power and broad compatibility.
Ideal for new or replacement installations, this transformer supports smart video doorbells and wired chimes for enhanced convenience.
Ideal for new or replacement installations, this tri-volt transformer offers versatile voltage outputs for various wired doorbell chimes.

Voltage Output

16V/30VA or 24V/40VA
16VAC/30VA
8-Vac/10-VA, 16-Vac/10-VA, or 24-Vac/20-VA

Power Capacity

30 VA or 40 VA
30VA
20 VA

Compatibility with Smart Devices

Weather Resistance

Mounting Options

Outside standard electrical boxes
Clamp-on