Can 208V 3 phase run 220V 3 phase machine
Can 208V 3 phase run 220V 3 phase machine
(OP)
Hello, We're trying to diagnose why a test machine went down in our lab. The manufature has us doing some voltage checks and state the machine should run on 220v. In diagnosis we found that our building service is 208v. Since industrial electrical is far from my expertise, i'm trying to find out how much of a difference 208v is as compared to 220v. Not sure there is a simple answer with my lack on information! Anything would be helpfull at this time. Thanks





RE: Can 208V 3 phase run 220V 3 phase machine
What is the nameplate voltage rating of the motor and what voltage was actually supplier at the motor terminals? A 208 V supply may only provide 200 V at the motor when voltage drop is taken into account.
RE: Can 208V 3 phase run 220V 3 phase machine
Now given the sparse information you have provided we are assuming that you are talking about a motor.
What kind of machine is it?
Is it a motor?
What exactly does "went down" mean in this context?
Stalled, overheated, less than full stroke, blown fuses, burned out transformers, solenoids or motors?
Bill
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"Why not the best?"
Jimmy Carter
RE: Can 208V 3 phase run 220V 3 phase machine
rmw
RE: Can 208V 3 phase run 220V 3 phase machine
The machine is a EMA dynometer (Elecro-Magnetic Linear Actuator). Basically the fuse box feeds power to the machines power enclosure. Within the power enclosure are 4 amps that feed the 4 actuators of the Dyno's ram. The Dyno operated flawless one day, the next it would not operate.
We found all 3 70 amp fuses open circuit in the fuse box. Did a basic short to ground check at the box with negative results and installed 3 new fuses. As soon as we flipped the switch on, the fuses immediately opened. In contacting the manufacture, they insist something has changed. Like we moved the machine and miss-wired?
We are doing some step by step diagnosis with the manufacture at the moment. So far have disconnected the output connectors at the amp and checked resistance values between each phase of the motor coils. Which are to manufactures specs. The next step with be to disconnect input power to all the Amps, and then power them up individually to see whether the amps power up or not.
We don't have schematics or current/amp specs etc. But the manufacture advised to power the amps using 220VAC and we're running 208V. We didn't want them to point the quick finger at the fact we're using 208V. That was the purpose of the post...to get some feedback first.
Thanks again! This is actually becoming a cool learning exercise!
RE: Can 208V 3 phase run 220V 3 phase machine
RE: Can 208V 3 phase run 220V 3 phase machine
The Point is;
What is the voltage rating on the machine and what is the frequency rating?
Is this North American made or European Union made?
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Can 208V 3 phase run 220V 3 phase machine
I would immediately install boost transformers.
Even if it actually runs it could have a shortened life. Like 50% its normal life. Is that worth avoiding the cost of three wall hung transformers?
Keith Cress
kcress - http://www.flaminsystems.com
RE: Can 208V 3 phase run 220V 3 phase machine
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Can 208V 3 phase run 220V 3 phase machine
Keith Cress
kcress - http://www.flaminsystems.com
RE: Can 208V 3 phase run 220V 3 phase machine
RE: Can 208V 3 phase run 220V 3 phase machine
The problem you described, 3-70A fuse blowing, indicates there is dead 3 phase short or extreme overload ( machine is jammed). 208V instead of 220V would not be the cause of 3-70A fuse blowing.
Find the cause of th eovercurrent. Did this machine ever worked other than the one day you mentioned? How old is it?
RE: Can 208V 3 phase run 220V 3 phase machine
In Canada we supply many larger commerial buildings with 347/600V voltage and the building owners use their own step down transformers to provide their tenants 120/208V and in most cases it works very well. Smaller buildings may have 120/208V main supply from us
Problems are now occuring when globalization is forcing manufacturers to to create 1 piece of equipment that will function at 208,230,240V and it comes with a name plate voltage of 220V. A large well known food chain now has all new equipment rated at this voltage including bun toasters
CSA Standard CAN235 states that the voltage should be maintained between 94-105% or low voltage of 196V. Equipment now rated at 220 V is trying to operate at 89% of its nominal voltage (utilization voltage can be even lower). It is amazing how much slower the buns toast at peak time around dinner when the utility voltage is at its lower levels.
We now see more printing equipment,gas station fuel pumps, HVAC equipment with this nameplate voltage being used on 3-phase and 240 single phase supply voltages and they are failing or burning out
We now tell customers with 600V to contact their vendor and possibly look at installing drycore transformers to match the voltages specifically for these loads
208V customers have to look at more epensive options. Equipment owners have to look more closely at this problem before the equipment is installed and put into service
RE: Can 208V 3 phase run 220V 3 phase machine
Half the time 208 is only really 19x anyway.
rbulsara; It could be that the machine has stalled and so those fuses are going on each start attempt.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Can 208V 3 phase run 220V 3 phase machine
RE: Can 208V 3 phase run 220V 3 phase machine
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If we learn from our mistakes I'm getting a great education!
RE: Can 208V 3 phase run 220V 3 phase machine
RE: Can 208V 3 phase run 220V 3 phase machine
robertb671,
Please post the motor nameplate information, and if not accessible, a better description of what you have. If by "amp" you mean an amplifier, then all of the discussions about motor voltages are essentially moot. But low voltage may in fact still be an issue for you, just for different reasons. In powering a servo, the AC power must be rectified to DC (that s what the "amp" does). In that process, there is usually a short surge of current as the DC bus is charged. But since you are only feeding it 208V, the lower voltage will result in higher input current and is possibly exceeding the instantaneous rating of your fuses.
Another possibility is that you have the wrong type of fuse. If the equipment was made in Europe or some other IEC country, the types of fuses they use are difficult to attain here in the US (assuming you are here because of the 208V supply) and your electrician may have not carefully investigated the fuse type he should use; happens quite a lot actually. Look at the numbers on the fuse and post them, then find out what specific fuse the manufacturer says t use. Some of us will be able to tell you if you have the right kind or not.
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RE: Can 208V 3 phase run 220V 3 phase machine