Hypertherm powermax65 Manual

5
POWERMAX65/85 SERIAL COMMUNICATION PROTOCOL
Last bit – Least
significant bit
(LSB)
1 bit sign
+/- at
MSB
Decimal point at
specified bit from
LSB, for example, 6
bits decimal.
8 7 6 5 4 3 2 1
First bit – Most
significant bit
(MSB)
Variable Scaling
In addition, Hypertherm uses variable scaling on some of the values as defined below:
Calculating the checksum (LRC)
ModBus ASCII requires a longitudinal redundancy check (LRC, also called a checksum) on each message.
NOTE: In the example below, and throughout this document, when you see 0x, the characters following the 0x are
hexadecimal (hex) numbers.
To calculate the LRC:
Example: :010108080001ED0D0A – the LRC is 0xED
Add the hex values of the message but exclude the start (:) and end characters (0D0A) and the LRC itself:
0x01 + 0x01 + 0x08 + 0x08 + 0x00 + 0x01 = 0x13
Subtract from 0xFF: 0xFF - 0x13 = 0xEC
Add 1: 0xEC + 0x01 = 0xED
The power supply responds to commands with either the ModBus function code and data, or with a ModBus exception
function code followed by an error code. For a list of the Modbus function and exception codes, see
http://www.modbus.org/docs/Modbus_Application_Protocol_V1_1b.pdf.
16 15 14 13 12 11 10 9
After the CNC takes control of the power supply, the switches and adjustment knob on the front panel are disabled, and
the LCD displays the remote control icon:

Hypertherm powermax65 Specifications

General

Brand	Hypertherm
Model	powermax65
Category	Welding System
Language	English