Ab Variable Speed Controller

I have a conveyor with AB variable speed controller 160 SSC .
The required voltage for the unit to operate is 460 v 3 phase and the motor is also 3 phase 460 v. My question is that can the unit operate at 480 v 3 phase and if so what will be effect of higher voltage applied to unit and motor. The motor FLA is 1.1 A . Thanks

PLC Boy,
Yes you can operate the drive and the motor at 480 volts. Your actual measured voltage is probably closer to 480 than 460 volts. A higher voltage will mean lower current, which will allow the motor to run cooler, within limits. Generally you can go + or minus 10 percent of "normal" voltage will no bad effects. I have seen 460 volt motors running as high as 500 volts, and as low as 440 volts. If you set the drive for 480 volts input, and tell it that your motor is 480 volts, then everything should match.

The nameplate value on motors, variable speed drives, and other power-using devices mostly tells you what is the LOWEST voltage that the device will operate with, while the nameplate on transformers, starters, and generators will tell you the HIGHEST voltage that the device is rated for or will produce.

I would recommend entering the motor nameplate data into the drive exactly as the nameplate reads. So if the nameplate says 460V, enter 460V.

That does not mean that the drive input is limited to that, however. Check the drive data page in the instruction manual. It probably says 460V +/- 10%. That will get you to 506V. Many imported drives will have an even wider input voltage range due to the need to cover world applications. They will sometimes be as wide as 380-500v +/- 10%.

On most V/Hz drives, when you set the motor nameplate voltage and Hertz, that defines the slope of the V/Hz curve. If you enter data different from the nameplate, the whole curve, from 0 to base speed will have the same % error. There are rare cases where this is done deliberately to alter motor torque behavior but that is not for mainstream applications.

ab 160

You should enter the real input voltage in the parameter. Because, the Over/Under fault can appear.

Berni,
I agree, if your real-world voltage is running from 480 to 500, (which I have seen far more often than the 460 volt level), but you tell the drive it is "theoretically" dealing with 460 volts, then those pesky little overvoltage faults can pop up. If they didn't want you to put in the real voltage, why put in a parameter to change it? What is the penalty for lying to a drive? If you tell it 460, and the actual voltage is 480, how does that help the drive any?

DickDV, I am sure that is what the book says to put in, the motor nameplate data (nameplates are never wrong, right?) but somehow I never seem to have a boss who will accept that as an excuse when the plant shuts down. Again we may be talking about two different things. There are some brands that specifically request "Motor Nameplate Voltage" or "Base Voltage". But most ask for "Maximum Voltage", or "Input Voltage". How could I fib about something that clear?

We have kind of got off-question here. PLC Boy did not even ask about entering the voltage in the drive parameters, but rather what will be the effect of a higher 480 voltage compared to 460 volts. I still say it will be a lower current.

Ok, guys, I went out to the AB website and downloaded an instruction manual for the 160SCC.

On page 5-6, the description of parameter 36 is Base Voltage and clearly says motor nameplate voltage.

Also on page 5-6, parameter 37 is Maximum Voltage which must be equal or higher than Parameter 36. You can conclude that the slope of the V/Hz curve is set by Para 36 and Para 35 (Base Frequency).

On page 6-2 Table 6.A Fault Descriptions under Overvoltage Fault it states that the Fault will occur at DC bus voltage of 800 which is approx equivalent to 575V AC. There is no mention of this level being modified by any software parameter.

On page A-1, Table A-2, Operating Input Voltage Range 340-506VAC. There is also no mention of any variability in this due to software settings. Note also that the DC bus trip level is way higher than the highest operating voltage of 506. This makes it unlikely that a high voltage fault would occur due to the AC line except for spike or noise conditions.

I conclude from the above that the setting of Parameter 36 has no effect on the input voltage tolerance, only the output V/Hz curve.

On the other hand, I know that there are drives out there that do vary the input voltage fault tolerance with the setting of the motor nameplate voltage parameter. Unfortunately, I must confess that ABB has engaged in this nonsense and has, only recently, done away with it. Other mfgr's also do this and it is the work of a diabolical design engineer somewhere insulated from real-world conditions.

The good news, as far as I can tell, is that the AB 160SSC is not one of those rascals.

AB VARIABLE SPEED CONTROLLER

HI GUYS
Thanks for the reply very much appreciated