IMP PUMPS NMT Max C - Page 5

6
Modbus specifications
Data protocol
Modbus RTU
Modbus connector
Screwless terminals
2+1 pins. See section 7.3 “ Connection to Modbus ”.
Modbus connection
type
RS-485
Modbus wire
configuration
Two-wire + common
Conductors: A, B and COM (Common).
See section 7.3 “ Connection to Modbus ”.
Communication
transceiver
Integrated, 1/8 of
standard load
Connect either via passive taps or daisy chain.
Maximum cable
length
1200 m
See section 7.5 “ Termination ”.
Slave address
1-247
Default is 245, settable over Modbus. See section
7.4 “ Speed, parity and address ”.
Line termination
Not present
Line termination is not integrated. For low
speed/short distance, termination can be omitted.
Otherwise, terminate the line externally on both
ends.
Supported
transmission speeds
1200, 2400, 4800, 9600,
19200, 38400 baud
Settable over Modbus register [default=19200].
Start bit
1
Fixed.
Data bits
8
Fixed.
Stop bits
1 or 2
1 stop bit minimum, up to 2 when parity not
enabled [default=1]
Parity bit
Even/odd/none
[default=Even]
Modbus visual
diagnostics
LED2
Flashing yellow when data reception detected.
Combined (OR) with Ethernet ACT function.
Maximum number of
Modbus devices
247
Limited by possible Modbus addresses to 247. 1/8
nominal load enables 256 devices.
Maximum Modbus
packet size
256 bytes
Including address (1) and CRC (2) bytes.
Isolation
Common ground (COM)
with SET1, SET2 and
SET3.
Modbus shares common ground with other signals.
Ethernet specifications
Ethernet connector
RJ-45
10BASE-T, 10Mbit/s connection.
Connection type and
services
- Web server (port 80)
- Firmware update over web interface
- Optional Modbus RTU over TCP/IP
Default IP address
192.168.0.245
192.168.0.246 for right twin pump.
Ethernet visual
diagnostics
LED1 / LINK
Slowly blinking when module is powered,
permanently lid when link established.
LED2 / ACT
Flashing yellow when data reception detected.
Combined (OR) with Modbus data reception
indication.
Mode selection switch
Adjustment
10 position rotary
switch
Position read at power-on.
Used for relay configuration and module
configuration reset.