13 best elk thermostats

Product description

Lighting/Thermostat Interface and Serial Port Expander for use with M1 system integration

• Adapts the M1 Control to many brands of Lighting control products which use "serial" communications. I.E.,OnQ-ALC, PCS-UPB, Centralite, etc.
• Adapts HVAC Communicating Thermostats from RCS, Aprilaire, and HAI to the M1 Cross Platform Control
• Expands the RS-232 Serial Ports of the M1 Control
• Operates from the M1 Data Bus
• DIP Switch Address Settings

Product description

No more doorbell/ thermostat underpower hassel:

24V 40VA Plug in transformer, replaces and upgrades underpowered transformer with this 24V AC transformer, offering plenty of power for your thermostats and doorbells.



Specification:

Input voltage: 120 VAC, 60Hz

Output voltage: 24V, 40 VA



Safe and stable:

Auto-resetting (PTC) fused secondary

LED green power indicator

Positive/negative/ground screw terminals



UL certified:

UL certification passed



Easy installation:

Electrical outlet mounting tab



Universal compatibility:

This 24v transformer is compatible with Ring video doorbell, ring video doorbell 2, Ring video doorbell pro, Nest Skybell doorbell, also compatible with Nest, Ecobee, Honeywell and Sensi smart thermostats, and other devices that require constant 24 volt power for operation.



Note:

The brand above is only for demonstrating compatibility.

• ELIMINATATE DOORBELL/ THERMOSTATS UNDERPOWER HASSEL: 24V 40VA plug in transformer, replaces and upgrades underpowered transformer with this 24V AC transformer, offering plenty of power for your thermostats and doorbells
• SPECIFICATION: input voltage: 120 VAC, 60Hz; Output voltage: 24V, 40VA
• SAFE AND STABLE auto-resetting (PTC) fused secondary, LED green power indicator, positive/ negative/ ground screw terminals
• UL CERTIFIED AND EASY INSTALLATION: electrical outlet mounting tab
• UNIVERSAL COMPATIBILITY: this 24v transformer is compatible with Ring video doorbell, Ring video doorbell 2, ring video doorbell pro, Nest Skybell doorbell, also compatible with Nest, Ecobee, Honeywell and Sensi smart thermostats, and other devices that require constant 24 volt power for operation; Note: the brand above is only for demonstrating compatibility

User questions & answers

Question:	Green Indicator light is no longer on. And ring doorbell stopped working after 3 months of perfect performance. What could be the cause
Answer:	You need to install a 50 W 25 Ohm Resistor.
Question:	is this a constant supply of power? Thanks
Answer:	Yes
Question:	Is it normal for the transformer to get pretty warm to touch
Answer:	The surface temperature of the transformer can reach 140 degrees Fahrenheit during operation, which belongs to the normal temperature range. Please do not touch it with your hands.
Question:	What is the guarantee on this item
Answer:	Any questions, please feel free to contact us by buyer seller message on Amazon. We'd like to help you solve the problem.

• POWER UP MULTIPLE THERMOSTATS / DOORBELLS: replaces and upgrades underpowered transformer with this 24V AC transformer, offering plenty of power for single or multiple thermostats and doorbells at the same time
• UNIVERSAL COMPATIBILITY: this 24v transformer fits for Nest, Ecobee, Honeywell and Sensi smart thermostats; Also compatible with Ring Video Doorbell, Ring Video Doorbell 2, Ring Video Doorbell Pro, Nest Skybell Doorbell, and other devices that require constant 24 volt power for operation
• SPECIFICATION: Input is 120 V/ AC, 60 HZ; Output: 24 V/ 40 VA
• UL CERTIFIED AND SAFE USE: this 24 volt transformer is UL-certified, offers reliable performance
• EASY TO INSTALL: screw down or threaded clamp to electrical box, simple to wire up; Please note: the brand names above is only for demonstrating compatibility;

User questions & answers

Question:	The unit states on the device to mount in a metal box only. My current device was in standard wall plastic junction box behind door chime. Work
Answer:	Yes it will. The requirement for a metal box is because the unit throws off a little heat and could, under certain rare circumstances, melt the box. Your doorbell or chimes is highly unlikely to pull enough power to heat the unit enough to do that. Why not install the unit, inspect it after an hour, 4 hours, 12 hours, 24 hours and a week. I’m sure you’ll find no indicia of heat damage. If you’re really concerned, replace the box.
Question:	There are 2 points, labeled "R" and "C", on the transformer where you attach wires with screws. What do "R" and "C" stand for? "Remote" and "Chime
Answer:	Two terminals R and C, they can connect any cable, beacuse this is AC power.
Question:	I have a nest hello, and i have had a problem with power. this product was suggested to me, but, what chime could i use
Answer:	You should be able to use it with any chime that requires 24V power.
Question:	I have bought this transformer, it says it is 24v. i am reading 30v at the doorbell button. anybody know if it will cause a problem with a ring pro
Answer:	24 vac transformers normally put out 28 - 30 volts. Any doorbell transformer that I have ever replaced is a 15 volt output transformer.

Product description

Elk 24 VAC 40 VA resetting transformer

• Input Voltage: 120 VAC, 60Hz, .43A, Output Voltage: 24 Volts A.C.
• Auto-Resetting (PTC) Fused Secondary
• Green Power On LED, Grounding Prong & Terminal
• Electrical outlet mounting tab
• H = 4.14-Inch, W=2.74-Inch, D = 2.2-Inch.

User questions & answers

Question:	is this 24 volts ac or dc? the desc says 24vac, under this question about current, says dc
Answer:	The label didn’t say about ph level. It says no added phosphates, phthalates or chlorine. Indeed or take: water, cocamidopropyl betaine, anhydrous citric acid, natural fragrance
Question:	Planning to use this for my ring video doorbell. ring indicates maximum voltage of 24. does this transformer measure 24v or less
Answer:	I believe it is due to it does not have harsh chemicals like other cleaning products.
Question:	Which pin does the GND connect to on the thermostat
Answer:	I have used it on my granite counter tops without any issues. It does leave a slight film that can be whipped off easily but does not leave a shiny finish like the specialized granite top cleaners do.
Question:	Technical details says dimensions of 8x4x6 inches - seems bulky - is it true
Answer:	To be honest with you, I’m not sure. It is a fantastic product!

Product description

ELK TRG1640 AC Transformer 16 5VAC 45 VA

• Auto-Resetting (PTC) Fused Secondary
• Green Power On LED
• Grounding Prong & Terminal
• Electrical outlet mounting tab
• UL Listed, Wire Strain Relief, Lifetime Limited Warranty

User questions & answers

Question:	Can this be used for Nest Hello doorbell
Answer:	Yes. Your tubs will shine beautifully.
Question:	Could this feed and run two Ring Doobell Pros at the same time
Answer:	Es producto excelente para la lompirs
Question:	I have been looking for a step/down transformer input 110 volt a/c to 12 volt a/c output, can you point the way
Answer:	This is a 12 to 1 mixture. I put mine in a spray bottle, spray the tub, then wait 5-10 minutes and scrub off.
Question:	I am needing to power my ring doorbell directly to a low voltage 8-24vac transformer. will this work? is there a preferred wire to use
Answer:	No yo limpio los vidrios de las bañeras es bueno

• WIDELY USE: US power cable Powers your popular smart thermostats((Nest, Ecobee, Honeywell, Sensi) and doorbells(Ring Video Doorbell, Ring Video Doorbell 2 & Ring Video Doorbell Pro,Nest Skybell , etc.) and other devices that require constant 24 volt power for operation, enables you to charge your devices safely.
• EASY TO USE:Assemble along the wall from your outlet to the doorbell and thermostat without the existing doorbell or wiring. Easy installation and be able to set up in minutes.
• LONG CABLE:Our cable is 8M(315 inch) long and you do not worry about the distance between the socket and the Honeywell Smart Wifi Thermostat. This allows you to easily plug it into an electrical outlet inside or outside your house.
• SAFE AND CONVENIENT :Our battery backup has gotten certificate. A quick fix to the problem of "Low batter" you can charge it directly(plug adapter into outlet and power up). that means you don't need to remove your honeywell thermostat in order to charge up the battery.With an AC output of 24V/500mA, a perfect tool to meet your needs.
• CUSTOMERS:WHAT YOU GET- 1. High quality accessory 2. 180 Days money-back 3 . Professional customer service. VIIVRIA has a professional team which has been specialized in designing and manufacturing transformers for a few years, improving technologies to meet consumers' needs.

User questions & answers

Question:	Can i run two thermostats with one C wire transformer
Answer:	You would have to discuss this with the company that makes them. However, the dependency would be the power drawn from each thermostat - if they are the new low energy types it may work. The only problem would be the wiring.
Question:	This becomes an exposed wire that runs to your thermostat
Answer:	The "exposed wire" are leads that you connect to your thermostat, or video doorbell. They're not exposed once you connect them.
Question:	Will this work with the vine 610 thermostat
Answer:	This will work with any thermostat. It simply provides the 24V power needed assuming your tstat wire and doesn’t have the additional wires for 24v power. Most furnaces have the 120/24V transformer, but older homes tstat wire never had enough conductors. Newer homes should. Regardless, yes, this transformer with work.
Question:	Does this work with the ring doorbell
Answer:	If you use this with the Ring 2 be sure to check the instructions on the Ring website (https://support.ring.com/hc/en-us/articles/205180710-How-to-Connect-Your-Ring-Video-Doorbell-Directly-to-a-Low-Voltage-Transformer-Without-a-Pre-existing-Doorbell-) for connecting to a power supply without a doorbell. To keep from damaging the Ring a 25 Ohm resistor needs to be added between the charger and the Ring, mine worked for about a week before the Ring quit accepting the charge. My Ring still works, but won't accept a charge or activate a doorbell.

Product features

Wild Using

This is a device that you can keep your machine continuously charging your doorbells or thermostats. Many old homes or apartments do not have a "C" wire to their current thermostat, and newer devices require a C-wire to power the device.This simple product allows you to make the problems

Continuously Charging

It can be continuously charging your device without the worry of take of the doorbells or thermostats. Which is time saving and work saving.

Package Included

1 x Adapter 24v transformer for thermostat 1 x 315 inch long cable (800 cm)

Long Cable

315 inch long cable (800 cm) allows you to wire it anywhere you want.

Specification:

• Inner size: 5x 6.3 cm
• Box size: 10 x 5.5 x 8 cm
• Input: 120V AC 60Hz 0.2A
• Output: 24V AC 500mA
• Cable length: 800 cm ( 315 inch)
• Wire Type: Stranded copper wire

• 24V C WIRE POWER ADAPTER: plugs into your standard 110 v/120 v outlet and converts to 24 volt AC current
• 24 VOLT TRANSFORMER FOR THERMOSTAT AND DOORBELL: powers up smart thermostats for (Nest, Ecobee, Honeywell, Emerson Sensi, Hive, etc.) and doorbells (Ring, Nest Hello, Skybell, August) that require 24 volt power for operation
• UL certified: UL certification passed, stable and durable operation 24V transformer
• EASY INSTALLATION: 2 pin non-polarity wires support easy and quick install, 23 ft cable is long enough to plug it into an electrical outlet inside or outside your house
• PACKING LIST: 1 x C wire adapter, 1 bag (50 pieces) of cable clips; Note: Please add a 50W Watt 25 Ohm Resistor if you use this transformer to power a doorbell. The brand mentioned above is just for demonstrating compatibility

User questions & answers

Question:	Is this a two prong plug or a three prong (w/ ground) plug
Answer:	Contact the seller or Amazon customer service.
Question:	I currently have r&w with a jumper from r to rc.i have a nest that needs c & doesn't have rc.what do i do with2ndwire?googles manual doesn't help
Answer:	Can't
Question:	I want to know if i need a 50w 25 om resistor when use this transformer to power a nest doorbell
Answer:	According to manual, its Rc and C that you will need to connect
Question:	Will this work for Ring pro compatibility
Answer:	Sure you can ,welcome your purchase

Product features

Upgrade underpowered devices

UL certified, safe operation

23ft cable with gift cable clips

For thermostats

1. Cut off the power of circuit breaker.

2. Install the wire from your 24 volt adapter to the “C” terminal and the other wire to the “RC” terminal. You need to use included jumper and connect from “RH” to “RC” terminals，if HVAC system has a cooling.

3. Plug the power adapter into the socket and turn on the power of the circuit breaker.

4. Install the panel on the thermostat.

Product description

Specifications: input voltage: 120 V AC, 60 hz, output voltage: 24 V AC at 40 VA, dimensions: 2 x 2. 5 x 2. 5 inch universal powering for multiple doorbell chimes, smart video doorbells and thermostatic devices in one home. Replace the old and under powered doorbell transformers for better performance. Compatible with Ring Pro and ring doorbells, Wi-Fi and other smart thermostats like Nest and Eco bee and more. Not compatible with ring chime pro. UL Certified to safety and quality. Safe and easy install I on. WARNING: This product may expose you to chemicals known to the State of California to cause cancer or reproductive harm

• 24VAC/40VA doorbell transformer for powering single or multiple doorbells and thermostats.
• Thermal cut-off switch offers an extra layer of safety, shutting off power in the event of excessive temperature. UL Certified.
• Quick and easy installation: simply mount to electrical box via threaded connector or screw down
• Eliminate issues caused by underpowered transformers: a lack of power, connection issues, low quality video resolution, and low chime volume may be an indicator of an underpowered transformer
• Compatible with Ring Video Doorbell Pro, Nest Hello, Nest thermostats, Zmodo Smart Greet Wi-Fi Doorbell, Sky Bell Doorbell, and more. Brands mentioned for compatibility information only.
• Input voltage: 120 Vac, 60Hz | Output voltage: 24 Vac at 40VA
• Backed by a 2 year manufacturer

User questions & answers

Question:	Desrciption mentions "thermal protection" will this work in my Houston area attic that routinely gets to about 120 degrees in the summer
Answer:	It puts out 24 vac with 120 vac input, if your house voltage is lower, say 115 vac it will put out 23 vacit is an unregulated supply so it will probably read a little high unloaded. It will be just fine for a doorbell circuit.
Question:	dos it have to be intalled in a metal box? Or can attach it on a sefase with screws
Answer:	For a WiFi thermostat, the 24v pair of wires connect to C and RH (or R) according to this video.http://www.youtube.com/watch?v=8a_f2_iAW1U
Question:	Is this polarity sensitive? Looking for R contact
Answer:	is not as bulky it says- is just around 3x2.5x2.5 inches

• POWER SMART DEVICES: This C-wire kit efficiently powers your smart WiFi thermostats from popular makers such as Honeywell, Nest, Ecobee, Emerson Sensi and serves as a doorbell transformer for Ring Doorbells, Nest Hello, Skybell, etc. No more low or dead batteries
• STANDARD HOME USE: Plug in transformer uses standard 110v outlet to convert to 24 volts of AC Power
• EXTRA LONG CABLE – 25 foot cable for added flexibility of long distance installation, easily hide behind baseboards and moldings.
• EASY INSTALLATION – 2 pin non-polarity wires to ensure easy and error free installation for installers of all skill levels
• WHAT'S INCLUDED – 24 volt adapter, 20 wall cable clips, optional jumper wire and lifetime no hassle replacement warranty

User questions & answers

Question:	Does this connect to the furnace board or thermostat
Answer:	Nest has two skills that allow its devices to work with Alexa's voice controls. With the Nest Thermostat skill, for instance, you can ask Alexa to change the temperature of your home. And with the Nest Camera skill, you ask Alexa to show video from your Nest camera.
Question:	Does this work with ecobee
Answer:	It so you can put it in another room and monitor and control the temperature in the different room instead of at the main thermostat.
Question:	Hello, I gather this is for a no c wire thermostat. I have a Red and white and they get connected to the new red and white...which do these connect to
Answer:	Yes, mine came with a wall plate.
Question:	I don't have a c post in my furnace, but i do have a c wire in my walls. can i run this to my furnace and connect it to my c wire and r post
Answer:	The sensor is wirelessly paired with the thermostat during the set-up process.

Product features

Who Needs This?

Anyone looking to upgrade to a new smart wifi thermostat or doorbell but your home does not have the necessary wiring to power these devices. Many older homes and apartments do not have a "C" wire to their current thermostat, and newer devices require a C-wire to power the device.This simple product allows you to:

How Do You Use This?

1. Shut off power at breaker
2. Install any wire from your 24 volt adapter to the "C" terminal and the other wire to the "RC" terminal. If HVAC system has a cooling you may need to use included jumper and connect from "RH" to "RC" terminals
3. Plug power adapter into outlet
4. Turn power on at the breaker
5. Attach face plate to your thermostat

For Doorbells

1. Keep adapter unplugged
2. Install wires from 24 volt adapter into the terminals for your doorbell unit (any wire can be connected to any terminal)
3. Plug adapter into outlet
4. Put doorbell face plate on housing unit
5. Power up and verify your doorbell is receiving necessary power using the accompanying application

24 Volt C-Wire Thermostat and Doorbell Adapter

Power adapter with 25 foot cable

Instruction Guide

Easy to follow step by step instruction guide

Jumper Wire

Optional use jumper wire included if your wiring setup requires it

Product description

Quickly solve the problem of "thermostats low battery"

Charge for thermostats directly, without needing to remove your thermostats to charge up the battery.



Universal thermostats compatibility:

Compatible with Nest, Honeywell, Ecobee, Hive, Emerson Sensi, etc..



Specification:

Input voltage: 120 V/AC, 60 Hz;

Output voltage: 24 V, 0.5 A/ AC

Length: 23 feet/ 7 m



Package includes:

1 x 24 Volt adapter

1 Bag (50 pieces) of cable clips



Note:

This is a compatible spare part and the manufacturers' names has been mentioned above for reference purposes only.

• 【24V C wire power adapter for thermostat】: plugs into your standard 110v/ 120v outlet and converts to 24V, 500mA/AC
• 【Designed for thermostats power supply】: widely applied for thermostats, powers up smart thermostats for Nest, Ecobee, Honeywell, Emerson Sensi, Hive, etc.; Charge for thermostats directly, without needing to remove your thermostats to charge up the battery, convenient and practical to solve the problem of "thermostats low battery"
• 【UL certified】: UL certification passed, stable and durable 24V transformer for thermostats
• 【Easy installation】: 2 pin non-polarity wires support easy and quick install, 23 ft cable is long enough to plug it into an electrical outlet inside or outside your house
• 【Packing list】: 1 x C wire adapter, 1 bag (50 pieces) of cable clips; The brand mentioned above is just for demonstrating compatibility

User questions & answers

Question:	Whats the VA output
Answer:	12VA
Question:	How can I bypass the pin
Answer:	Please refer to the third picture on product page. This is 24V AC voltage, the two pin don't need to distinguish positive or negative.
Question:	this isn't powering on my system, what am i doing wrong? i have one wire in the c, and and on in the rc all other wires in the correct place
Answer:	Check the power supply when I did exactly what you did on placement of the wires then flip the breaker it came on for me. Faulty power supply, faulty thermostat I would recheck wires again
Question:	Does it have any country restriction
Answer:	applicable to US and Canada, not applicable to other countries and regions.

• 【Gravity induction switch】 Easy to use, no need to turn it on/off manually. The product is used for heat preservation and does not have the function of boiling water.
• 【Night indicator】 The Indicator light will be on when mug warmer is working. So you can find your drink without turning on the light at night.
• 【Use Suitable Mugs】 A thin-walled, flat-bottomed mug will have the best warmth retaining performance.
• 【Safe & Durable】 FCC & UL certificated. The spill-proof design avoids damage and makes cleaning a breeze.
• 【Best Gift Choice】 Beautiful and compact design, easy to take anywhere, it will be your best gift choice on Thanksgiving, Christmas or other special occasions.

User questions & answers

Question:	there is no plug. at end of the cord, there is a flat metal thing which is larger than a computer uses. How do I get power too the coaster
Answer:	It is possible that you can run multiple doorbells with this assuming that its an 8 - 24v doorbell. Wired in series.
Question:	Does it come with the mug
Answer:	This is a 16.5v ac transformer. With no load, the output voltage is closer to 19v.
Question:	Does this work from 220v
Answer:	Will work great. If you get a 3 terminal model just use outside 2 terminals though or the voltage will be too low. Equipment is Very low voltage/current so normal door bell wire is fine (I actually used old copper telephone wire.... remember the old telephones used to ring at about 100v AC and had over 24vDC on the line all the time)
Question:	Is the mug dishwasher safe
Answer:	It is basically a furnace part. Transformers are used to change ac voltage. In this case, 120 line voltage is lowered to 24-28 volts ac.

Product features

Luminous Mug Warmer

You only need to put the cup on it, the indicator light will turn on, it will automatically turn on, instead of manually opening/closing, the temperature is just right.

131℉ constant temperature

It can be used for any hot beverage, such as coffee, tea, milk or hot cocoa.

Always keep hot coffee or tea at a potable temperature (131℉ / 55℃).

Waterproof design

The splash-proof design can avoid damage, making cleaning easy, safe and reliable.

Night indicator light

The Indicator light will be on when mug warmer is working. In this way, you can find drinks without turning on the light at night. If you work and study late, it still provides you with warm hot drinks.

Warm at home

It can also accompany you to spend a relaxing afternoon tea time. Even if you have a task or work to take care of at home, you can still enjoy mellow hot coffee.

Exquisite packaging

As a gift to family and friends, it must be a surprise! Suitable for all coffee lovers, this is the most intimate gift for dear friends or beloved family members.

Product description

You’re a busy person with numerous devices to remember how to use. But with its familiar “Honeywell Home Round” design and enlarged scale making it easy to see, the CT87 Round Non-Programmable Thermostat is not one of them. It’s the world’s most popular thermostat design and will fit perfectly in your lifestyle and your home.

From the Manufacturer

The Round Manual thermostat by Honeywell is the world's most popular thermostat - installed in over 70 million homes and buildings. This CT87K heat only model provides precise accurate performance with the ease of use that you've grown accustomed to - simply turn the dial to desired temperature and let the thermostat take over.

• Classic round styling; familiar design looks great in any environment
• The product is highly durable and handle
• Accurate temperature control of +/-1° F
• Easy to install and use
• Mercury Free

User questions & answers

Question:	I just need to replace the cover. Is the cover sold separately
Answer:	No. Cover not sold separately.
Question:	Will this thermostat work okay for replacing my King thermostat--line voltage double pole
Answer:	search for "line voltage thermostat" in tools and home improvement, there are several to choose from. For example "Honeywell Manual 4 Wire Premium Baseboard/Line Volt Thermostat(YCT410B1000/U)"
Question:	Is there a battery in ct87k
Answer:	What battery does it take? CR2050?
Question:	Is this a 2 wire hook up
Answer:	Yes, but it is not a contact closure thermostate. It is a millivolt, so it draws power from the line.

Product features

Honeywell Home CT87K1004 The Round Heat Only Manual Thermostat

Description:

With its familiar circular design and simple twist action, The Round Non-Programmable Thermostat makes setting your ideal temperature quick and easy. Plus, the popular thermostat design fits perfectly into your home.

Product description

This is a Endurance Pro 24V 40VA Thermostat and Doorbell Transformer, Power Supply Compatible with Nest, Ecobee, Sensi, Honeywell Thermostat, Nest Hello Doorbell and All Versions of Ring Doorbell.



Specifications:

Primary: 120V

Secondary: 24V, 40 VA Terminals

Input: 120V/AC, 60 HZ

Output: 24V/40VA

Compatible with: Nest, Ecobee, Honeywell, Sensi smart thermostats.

Fits: Ring Video Doorbell, Ring Video Doorbell 2, Ring Video Doorbell Pro, Nest Skybell Doorbell



Manufacturers’ part numbers are solely for identification. All materials supplied by us are our replacements for manufacturers’ parts. All product and company names are trademarks or registered trademarks of their respective holders. Use of them does not imply any affiliation with or endorsement by them.

• This SupplyEdge product is UL/CSA approved to assure safe operation and long life. Warranty- This part sold by SupplyEdge come with a 1 year, no questions asked, no hassle warranty.
• Powers thermostats and doorbells: replace underpowered transformers
• 24V 40VA fits Nest, Ecobee, Honeywell, Sensi smart Thermostats, Ring Video Doorbell, Ring Video Doorbell 2, Ring Video Doorbell Pro, Nest Skybell Doorbell and more
• Easy to install: screw down and thread clamps to electrical box
• Superior Quality you can Trust! This SupplyEdge Products is UL/CSA approved to assure safe operation and long life.

User questions & answers

Question:	If home classic doorbell is 16v, will this toast it
Answer:	I am in NW Houston and had no problem with mine in the attic over the summer.
Question:	Which doorbell wires hook up terminal r and which hook up to terminal c on the 4011mt transformer for the ring pro
Answer:	The 40vA door bell transformer is supposed to be properly installed on an electrical/receptacle box containing the power feed. If you're looking for some guidance, there are helpful instructional videos on YouTube.
Question:	How do you ground the transformer
Answer:	It is not polarity sensitive
Question:	Do you still need to use the included jumper wires with Eufy doorbell once you installed this transformer? Were you able to use you existing chime
Answer:	Don't own one but I looked up on Google for power requirements and found: "The nest hello doorbell requires 16V-24V." If this is correct then you should be good to go.