DH905 16V 10 Watt Doorbell Transformer for Wired Doorbells
16 Volt AC, 10 VA (watts) transformer. For use with single chimes, bells, buzzers, and other applications within specified ratings.
Wired doorbell transformers are electrical devices that step down the high-voltage electricity in your home to a lower voltage compatible with wired door chimes, wired doorbell push buttons, and most recently video doorbells such as ring.com and chime.
The power in USA homes is 120V, while a wired door bell requires 16V. Supplying that much voltage to your wired doorbell system would quickly burn out your lighted push button and break the chime. Therefore, you must have a wired transformer in your home to “transform” the electricity from 120V to 16V (most wired doorbell require 12V-16V).
The small table below shows the differently wired transformers we carry at 1800doorbell.com. There are various factors to consider when choosing a doorbell transformer, and the chart below simplifies choosing the right one. If you have a basic wired doorbell with a standard “ding-dong” sound, we recommend the 16V, 10VA transformer, the DH905, or the T1610. Using too much voltage is recommended and will break your doorbell.
In most situations, the Volt-Amps (VA) are most important. Most wired doorbell systems that use 1-2 lighted push buttons and 1 door chime box (that plays the ding-dong sound) will use a 10VA transformer. Unlike volts, oversizing VA won’t get you into trouble, as the door bell box will only pull what it needs.
The trouble typically arises when the transformer cannot supply enough VA for what is requested, which often leads to a humming sound or overheating of the transformer.
With the popularity of video doorbells camera systems like ring.com, chime, and others, require more amps than a traditional door chime. In most cases, assuming you are using the correct gauge wire and the run isn’t overly long, a 10VA transformer should be okay. Problems typically happen when using a video camera doorbell with a wired chime. In that case, we recommend the DH910, the tri-volt, or the 3TRAN doorbell transformer.
Although we do not offer the most extensive selection, the necessary bases are covered when installing or replacing your wired chime. We are often asked questions about using a wired doorbell with a Ring.com or Hello Nest video doorbell. We suggest you visit their support pages, but we offer this tidbit.
Video doorbells tend to use more amperage than a standard wired door chime. Coupling the video doorbell with your wired chime requires even more amperage, and most doorbell transformers don’t have enough power. We would recommend the DH910 for these purposes.
For a single doorbell installation, use one push button. One wire from the push button connects to the front door screw on the doorbell. The second wire from the push button is wired to the doorbell transformer.
Connect a wire from the terminal, common, or transformer screw to the doorbell transformer. Connect another wire from the transformer to the second wire from the doorbell push button.
For two push buttons with one wired doorbell, the setup is essentially the same with this difference. One wire from the second push button (back door, for example) will connect to the rear terminal screw on the doorbell box chime. A second wire from the second push button will connect to the wire from the first push button that leads into the transformer.
a tri-volt doorbell transformer allows you to use different voltage and VA options. If connecting two wired doorbell chimes OR connecting your Video Doorbell in conjunction with your wired doorbell, this is a great transformer to choose.