Electrical for appliances
cbut8995
| Posted in General Questions on
What does the following mean for appliances as my electricain told me to put down all of the amps and volts for our appliances and saw this for our wall oven.
120/240 V 60 HZ – 2800 W
208-240 V 60 HZ – 2100 W
16 Amp dedicated circuit
I was going to tell him to put a 20 amp dedicated circuit but do i tell him 120/240 or 208-240.
Thanks.
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Replies
IANA Electrician or an Electrical engineer, but...
Most US homes are fed with 120/240 service. When plugged into 120/240 service the appliance pulls 2800 W.
Most US commercial buildings are fed with 208/240 service. When plugged into 208/240 service, the appliance pulls 2100 W.
With either service, the appliance needs a 16 amp dedicated circuit.
Many newer induction cooktops, which are advocated on this site, need a 40 or 50 amp dedicated circuit. If you are having your electrical redone, now is the time to plan for induction. With a wall oven that may not be necessary, but if your cooktop is gas or electric, I'd make sure to equip it for a future induction cooktop.
Is there any downside for putting in a 20 amp circuit for this oven if in the future?
Yes, it's too small of an amp to support future electric only appliances. It's much more expense to redo the electrical later. So put it in but upgrade to a 50 amp (240) circuit now.
> Most US commercial buildings are fed with 208/240 service.
This is not true. The combination in question is 120/208 V three phase wye. This means that the conductors have a potential of 208 V between any two phase conductors and 120 V between any phase conductor and neutral.
Is there any real distance between the 120/240 V 60 HZ – 2800 W OR
208-240 V 60 HZ – 2100 W.
WHen you mean 240 circuit which should I choose then 208 or 120?
>"WHen you mean 240 circuit which should I choose then 208 or 120?WHen you mean 240 circuit which should I choose then 208 or 120?"
The electric company already "chose" for you. You get what you get. In almost all cases in North America, you will have 240v service to your home, and that's what voltage your oven will run on.
Bill
cbut8995,
With the equipment and manuals there, if your electrician can't figure this out, you need a new one and soon, I would not trust them to wire my place. Wiring a cooktop and wall oven is a standard work, there is nothing special about it. There are some code specific details which your electrician should know.
When in doubt about service sizing, breaker and wiring, read the manual.
You don't get to choose. Either your residence has 120/240 V split phase power (very likely) or 120/208 V three phase wye power (unlikely but possible). Your electrician will know which you have. Send them the installation manual of your oven.
The labeling you saw is a little confusing, but I'm pretty sure what they need. 2,800w at 240v is about 11.7 amps. The unit specifies "120/240V" because it probably needs a neutral, so it needs a 3 wire + ground cable, not a 2 wire plus ground. The neutral usually just runs the light and sometimes the control electronics, but if the unit needs it, you have to run it.
In the US, there isn't really a "16A" circuit, your choices are 15A and 20A. Code says you can't load a circuit up over 80% for loads of more than 3 hours duration, so they are probably telling you with the "16A circuit" that you need a 20A circuit installed to run your oven.
Typical ovens -- not ranges -- use no more than a 30A 240V circuit, except for some double ovens that may need more. What I would have your electrician do is to install a 20A breaker in your electric panel, then run 10 gauge wire (which can be "upgraded" to 30A in the future if you replace the oven), and use 3 wire plus ground cable, which will have a black, red, white, and bare wire in the cable. This way you have the 20A breaker that you oven needs, but 10 gauge wire to allow you to upgrade to a 30A circuit for a future oven without rewiring, and you have the neutral in the cable to get the "120/240V" service that the oven needs.
Cooktops and ranges (ranges are an oven and cooktop integrated into one unit) often need 40A or 50A circuits, but that's not the case here. I would *NOT* run a 50A circuit for a standard oven, and you should NOT put a breaker larger than recommended for the appliance since that can compromise the safety of the appliance. You CAN oversize the wire though, so that's how you put in your future proofing here, which is why I recommend using 10 gauge wire instead of the 12 gauge wire that a 20 amp circuit would normally use.
Bill