eufy video doorbell transformer specs for solo installation

I’ve read this entire thread and I’m more confused than I could ever think.

Is it really that far fetch to want to install this without having an old doorbell system?

The device itself say :
Input 1: 16-24V ~ 0.3A 50/60 Hz
Input 2: 19v = 0.6A

but nowhere in the manual is there anything about voltages,

I need to install this about 4fts away from a power outlet, So I guess I’ll just connect it to that 18v charger and cross my fingers. https://www.amazon.com/HQRP-Adapter-Transformer-Compatible-Doorbells/dp/B0897WGXWJ

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BTW, Nothing simpler than using almost any used laptop charger.

Any recommended transformers for the UK? all the ones I see above are US based

There is another thread for UK transformers…

I had the 2K wired doorbell connected to a 16V transformer, it worked for 2 months and the transformer died. I bought a 24V transformer and connected it directly to the doorbell. It worked for almost one week, then there was no power to the doorbell. Checked connections, everything was working fine (120V going into the transformer, 20V reaching the doorbell). Eufy Support sent me a brand new unit, connected it, no power. What am I missing?

I’m having the same issue as @sdp7. I have had this working since august with no issues with a 18v 10vA power supply and then the battery ran out on me. I checked everything and got another power supply 18v 40vA. Its not charging over the transformer. I had to unplug the doorbell and charge via usb. Today I was told that i did not need a resistor when wiring it directly without a chime. There are some variables that has happened all at the same time.

  1. There was an update on Feb 18, 2021 applied to the doorbell.
  2. I live in NY and battery does not do well in cold weather.
  3. I changed the power plan to custom to 45 seconds record time with 40 second re-trigger.

Chiming in… Dealt with this but on a ring branded doorbell, I suspect it’s the same here.

The doorbell is designed to use with an AC volted chime, but if there’s no chime you’ll need a resistor to imitate the load a chime transformer would normally have built-in. The doorbell is like an LED light and can’t run unregulated or it can become unstable / burns out the transformer or doorbell eventually / weird things also just happen in this form. Running a low amp AC wall transformer may work temporarily, but the doorbell will be asking for all the power it can get, significantly shorting the life of the transformer. The resistor though would help regulate the load. It’s possible there are wall transformers with the built in resistor too as a specialized item.

Keep in mind that when you push the doorbell button, you are directly shorting the contacts (to complete the circuit of the chime itself causing it to actuate, which is something you don’t want to do (short circuit) to a transformer without a resistor/load.

I suspect support doesn’t quite understand how the engineers designed it, but I also suspect they could release doorbells with just a DC in port option too for houses without a system already in place to simply keep them charged…

For a resistor, you’ll want something similar to this: https://www.amazon.com/Ring-53-023183-Wirewound-Resistor/dp/B07WF98SVW

Hope this makes a little sense. Let me know if I missed something.

Update:
So this is the second time my doorbell did not charge the battery and I had to disconnect from the transformer and charge up with a usb cable. My Power management mode was set to “Custom Recording” to 45 seconds record time with 40 second re-trigger these last 2 times that the battery drained.

This time I charged it up about 70% and changed the power manager to “Optimal Surveillance.” Before I attached the doorbell back to the transformer I noted that the battery was not fully charged. I waited a few days and unplugged from the transformer and saw the my doorbell was FULLY CHARGED now.

In my case it seems to an issue to setting it to “Custom Recording.” I wonder if most here have is set to custom recording. I saw one mention of it from @andrew.hosford post.

I now have is set back to “Custom Recording” with Clip Length to 45 sec and retrigger at 46 sec to see if the issue has do to with my re-trigger time being less than my Clip Length or if its just an issue with the Custom Recording option overall.

Necrothread FTW

sooo… i’m having the same issue/concern with my wired 2k doorbell. It worked fine all summer and fall, but now has died and seemingly has no power. there is definitely 20VAC coming from the xformer to the doorbell, and i have bypassed the legacy chime with the jumper included in the box. like i said, fine for the past 6 months, now no power. i dont know what VAC the xformer is, but the house was built in 2003, so i’d assume it was putting out enough power. now what about this resistor everyone is talking about? nowhere in the instructions does it say we need a resistor after bypassing the old chime. any more info on this? And what can i do to try to get my doorbell working again? Porch pirtates are rampant in the area, and seeing when deliveries get dropped off, especially this time of year, are pretty important.

Similar problem here. Wired 1080p working fine for 1 year, 3 months. Died on Sunday. 12v transformer from existing wiring. Multimeter shows still putting out 12v but doorbell is DOA. Eufy won’t replace because it is out of warranty (of course). Buying a new 2k to see if that works.

This is crazy. Eufy themselves are recommending two adapters that are way short of 30VA : https://support.eufylife.com/s/article/How-to-Hardwire-Your-eufy-Wired-Doorbell-without-an-Existing-Wires

While this is an older thread, it is the only one really dealing with the topic of powering the video doorbells using a wall plug in transformer.
I bought one of the two recommended adapters (the Viivria 24v AC 60Hz 0.2A input, 24VAC 500mA output transformer) and it seemed to work powering the E8210 2K Battery-Powered doorbell, but recently it registers as no battery power and shut down. Since then, I replaced the transformer to a Ohmkat 120V AV 60hz 0.3A input, 20VAC 500mA output one and the same thing.
Now I don’t have the electrical know how to convert 500mA to VA, but regardless, neither the plug-in transformer keeps the E8210 2K model or the E8203 Video Dual Wired doorbell fully charged up and both end up giving a low battery message.
It’s really frustrating not being able to get a direct response from Eufy as to which transformer would keep the doorbells from getting a low battery indicator. One would think that Anker being experts in power bank and power house supply would issue a official wall plug-in transformer for these doorbells.

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Can’t believe there’s still no “official” answer here. Post #9 says Eufy support says the resistor is required. Post #11 says (correctly) that the install manual only suggests shorting your legacy chime out of the circuit. Post #26 says Eufy claims no resistor is necessary.

Post #15 says that without the resistor, output from the transformer isn’t stable. Post #18 says his 40VA transformer is getting hot, due to underloading.

I think the confusion must be coming from the various combinations of legacy chime / no legacy chime, and wired Eufy / battery Eufy.

The wired Eufy page says: “the doorbell requires you bypass the existing doorbell chime. It’s as simple as connecting a jumper on the chime.” The battery Eufy page says: “Compatible with mechanical chime (not digital chime)”. This seems like it implies a fundamental difference in the power requirements between the two models.

I can only speak to the wired Eufy, which is what I have. But I don’t see why jumpering the legacy chime would require a resistor. If you look at the Eufy install manual, jumpering the chime would create a direct short between the transformer contacts. (As explained in post #27.) But this is not the case when the Eufy replaces the original doorbell button. Unless I’m missing something, the jumper essentially simplifies the entire circuit to two unbroken wires. And at the “button end”, there is no longer a simple contact switch - there’s a device (the Eufy) that accepts 24VAC. So no short circuit, unless the Eufy creates one - which it won’t, since it’s not expecting a legacy chime.

This same argument holds in the case where there’s no legacy chime at all. The wired Eufy isn’t compatible with a legacy chime, so presumably it’s “expecting” a direct connection to the transformer, with no additional load.

But the battery Eufy claims to be compatible with a legacy chime. So maybe it’s “expecting” that load - whether it comes from the legacy chime, or the resistor that mimics the legacy load. (Though the manual doesn’t say a resistor is required.) If the doorbell’s internals essentially mimic a legacy contact switch when the button is pressed, creating the short-circuit situation described above, then a resistor makes sense to me if there’s no legacy chime. (Note that if you google around, you’ll find a similar mess of answers for the Ring doorbell… Different models do/don’t require resistors.)

TL/DR: My electrical engineering degree is super dusty, but if someone knows a reason why the wired Eufy would require a resistor, when it’s expecting no load on the wire, please feel free to correct me.

(p.s. - my wired Eufy has been working well enough for 2.5 years with the 24V / 500mA transformer I linked in post #10. No legacy chime, no jumper, just wired right into the transformer. I haven’t checked the transformer for heat, though.)

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Yeah I can’t believe it either, especially since its a community forum on their website. Maybe no one from Anker reads the threads. Anyway, that is the same setup I had Mitch, (the 2K video doorbell and same wall plug in transformer) which I since changed to the dual video doorbell and a similar 24V /500mA wall plug in transformer. Both get the low battery icon in the amp.
I haven’t tried adding a resistor since I read that’s only if you don’t have a chime and the dual model I bought comes with one.
One thing you brought up that is on point

“I noticed that the AC-adapter-style transformer that Anker recommended above provides significantly less than 30VA. It’s 16V @ 800mA = 12.8VA”

and it’s so annoying that Eufy doesn’t clarify if this is for a home built in transformer or a wall plug in one. I assume it’s for the former.
After some research I finally figured out the v @ mA = VA formula and in the screenshot of the list below,
Eufy%20Recommended%20Transformers%20list
I’ve managed to put the wall plug in transformers I’ve bought so far (first 5 in the list) but they are way below the 30VA. The remaining ones on the list are close or over the 30VA recommended rating, but I’m debating whether to get any of the higher ones for fear that it would damage the doorbell.
Although I do have the Elk Transformer from the list being used in the basement to run my basement thermostat.
Edit: Just found one rated 16V@1810mA = 29.9VA (closest to the 30VA they recommend) but the install diagram shows a resistor on the doorbell side. So I updated the image.

Thanks for the chart! My gut is telling me that this confusion continues to be about the particular Eufy model (wired vs. battery), and how it’s installed - legacy chime, no legacy chime, or legacy chime that’s been jumpered out of the circuit.

For the wired doorbell, I suspect that ~12VA may be enough, since there’s no battery to charge, and no legacy chime to worry about. In my case, it has been. It makes sense to me that the battery doorbell would pull more power - both for charging, and especially if it’s hooked up to a working legacy chime.

But this thread is so long now, that I don’t have the energy (no pun) to collate all the positive/negative experiences. It would be great to have correct specs (power & resistor) for each of the models, and each of the wiring schemes. Anker - is this so hard?

I think the only concern about using too large of a transformer would be the stability and heat issues mentioned in #15 & #18 above. But again, this is speculation based on a 30 year-old electrical engineering degree. So someone with more current (again, no pun) knowledge can feel free to chime in (holy crap - I can’t stop myself with the puns!).

Wow! I just got my 2k batery doorbell with homebase 2 which I want to hardwire but not a legacy chime and am now frustrated and confused. I had a 24v 12va wallbrick I was gonna use, but ordered a 24v 40A. Now I think either the 12VA or 40VA may or may not work and/or damage it. But would a failsafe solution be to buy legacy chime. If I didn’t want it to chime, I could remove the striker/hammer. I was planning to use the homebase as my chime. But wouldn’t this fix the regsister issue? BTW, was there an answer as to whether the resister should installed in parallel or in series?

Check the manual - my memory is that the battery camera manual still said that the resistor isn’t necessary, despite the conflicting reports from Eufy customer service above. You could always file a ticket with them, outlining your exact situation.

I personally wouldn’t install a legacy chime just as a “safety”. Resistor would be cheaper & easier. I’d just make sure you buy one of the beefy resistor models linked above - if it is indeed necessary, it’s because it needs to dissipate a fair amount of power. I’m guessing series is the correct wiring. The only potential harm of installing an unneeded resistor, afaik, is if it drops the voltage too low for the camera. Which seems unlikely, and also easily checked with a multimeter.

But since your camera is still in warranty, you could always set it up with the Eufy-suggested transformer, no resistor (I think - see manual), and if the transformer gets hot or the camera battery doesn’t charge, etc. then at least you have recourse to get it replaced.

As always, if there’s someone out there with better electronics-fu than I, feel free to disagree.

I got a Heath Zenith wired “chime” off eBay for $12 which is about the smae as a resister. I may need this for another wired only video doorbell if I can’t resolve the Eufy issues.

A little off topic, but as for the manual are you referring to the 19 page quick setup guide? I was seeking a full user/owner manual for the T8210 but can’t seem to find one. Everything I have seen (such as the Amazon listing says a 10VA transformer is all that is needed for (only) the doorbell. A real manual would be so helpful. For instance, the 18 pager does not say anything about how to set this up with the homebase 2. I chatted with Eufy installation support and they could not find a link to one.

Yep - the one I looked at is here: https://support.eufy.com/s/product/a085g000004wZdhAAE/video-doorbell-dual-2k-(battery-powered)

No mention of a resistor, as I recall. Also no transformer specs.

Some specs from reddit: https://www.reddit.com/r/EufyCam/comments/rm66i5/2k_wired_doorbell_power_requirements Plenty of other posts on that subreddit as well. Report back if you find anything interesting

I only have a B.A. degree - not a BS one and certainly not an electrical one. i have a hard time understanding why a resister would help keep the battery charged. I also do not understand how not having chime would short out a transformer even if chime is selected or why selecting no chime would not prevent that. It would seem a resister constantly draws current and since it triggers that, it may be why it helps keep the battery charged but who knows if constant charging will eventually damage the battery. I think most chimes (if they have an electro-magnetic coil to activate the striker) only draw power when the circuit is completed so it may not help keep the battery charged but it is certainly how a properly designed doorbell should be able to work. A real manual that included a circuit diagram would be so helpful. There has got to be something missing as other battery powered doorbells also have a problem with keeping the battery charged. I ditched my Ring 3 Pro for that (it constantly went to 3% in a week requiring removal and a 12 hour USB recharge) , But battery Arlos are also said to have that problem. How hard is it to design a circuit that will keep up with all the great features and not just do an inadequate trickle charge. It may be that a wired only one is the only way to go to get set and forget to avoid the hassle of constantly having to attend to charging the battery.