I am trying to control the rate of rise (example: 5VAC/minute) of the output voltage of Autotransformer. What is the best way I can do this? Do they sell units that I can "tap a PLC into"?

 

What exactly is the application?
What supply voltage?

 

Hi,
precision rectifier AC/DC+ galvanic separator, - PLC. PLC to memorize the DC value and compare it with DC value one minute later.
Use the voltage transducer:

Voltage Transducer 0-300V AC In, 0-10V DC Out, DIN Mount - Denkovi A E LTD

 

I am trying to control the rate of rise (example: 5VAC/minute) of the output voltage of Autotransformer. What is the best way I can do this? Do they sell units that I can "tap a PLC into"?

Hi,

I would think an AC output converter that has adjustable output voltage would be a start, but they also make motor driven variacs you can use since you need a slow change in output voltage. I don't know the application though so that could be different.

 

Hi,

I would think an AC output converter that has adjustable output voltage would be a start, but they also make motor driven variacs you can use since you need a slow change in output voltage. I don't know the application though so that could be different.

Do you know who sells affordable motor driven variacs?

 

What exactly is the application?
What supply voltage?

The primary supply voltage is 120VAC. Is it then fed into a step-up transformer (kV output range) which its output (secondary) is rectified to DC. I would like to control the the primary supply voltage to have control of rectified kVDC.

 

Hi,
precision rectifier AC/DC+ galvanic separator, - PLC. PLC to memorize the DC value and compare it with DC value one minute later.
Use the voltage transducer:

Voltage Transducer 0-300V AC In, 0-10V DC Out, DIN Mount - Denkovi A E LTD

I believe I need the opposite of this. I need the PLC's 0-10 VDC output (INPUT) to control the 120VAC output (0-120VAC)

 

How much current do you need?
What is the load?

 

Hi,

I would think an AC output converter that has adjustable output voltage would be a start, but they also make motor driven variacs you can use since you need a slow change in output voltage. I don't know the application though so that could be different.

Part number for converter?
0-120VAC = variable output
4-20mA or 0-10VDC = voltage input

 

Look for the Ametek variac model NX1-260-16.
This is the first hit in Google, I am sure there are several more, including cheaper Chinese devices.

 

I am trying to control the rate of rise (example: 5VAC/minute) of the output voltage of Autotransformer. What is the best way I can do this? Do they sell units that I can "tap a PLC into"?

You find an autotransformer that meets your demand. Names like STACO come to mind. Large autotransformers are normally driven by Slo-Syn motors.

Ron

 

Do you know who sells affordable motor driven variacs?

Hi,

Sorry, not offhand but check the other replies before this one.
Always good to search anyway for most current offerings.

 

It sounds like the TS is asking for a servomotor controller for an equivalent to a Powerstat or Variac device. I was confused by the reference to "autotransformer" even though it is indeed technically correct.

Motorized versions of those have been available for many years, but most are adjusted by a 72 RPM synchronous motor. Vor a variable rate that will need to be either a stepper motor or a servomotor. Both are available with appropriate controllers.