Communications Notes for the MP Series Variac Variable Transformer Motor Control

Submitted byglx25v onFri, 08/17/2018 - 17:29
Switch Settings

To communicate the following switch must be set:
SW2-3 Needs to be set to ON


Communications Settings

As standard the communications settings are as follows.  Your communication device must match these parameters:

Baud:  9600
Data Bits:  8
Stop Bits: 1
Parity: None
Flow Control: None


Basic Protocol Requirements

1) You must send the complete message within 10 seconds or the control will return NAK (Negative Acknowledge).
2) You first need to put the controller in the "Listen" mode.  To do that you need the serial number (4 Digit code on the EPROM) or use the default code of 9999.
3) ^C is the "Control-C" character (ASCII character 03). 
4) Make sure the the sending device is not looking for handshake signals like DSR or DTR. 
5) An additional CR or LF should not be sent.


Common Communication Functions

Below is the message that needs to be sent to place the control in the listen mode using the default serial number of 9999.  You can replace the "9999" code with the four digit code that is on the EPROM:

LA 9999^C
 Note: There is a space between "A" and the first "9"
After the control is in the listen mode you can query or change the set point for the controller.
To read the present feedback voltage Phase A:

To change the target voltage Phase A to 115 volts the following steps are required:


ST1 115^C


The controller will repeat the received value:




To tell the controller to go to the target value in the table for Phase A.






Additional Information


User Manual for MP Series Control