Specifications Of Modbus ® Rtu Communication - Mitsubishi Electric EMU4-FD1-MB User Manual

Specifications of MODBUS
Item
Communication method
Protocol
Synchronization method
Transmission wiring type
Baud rate
Data bit
Stop bit
Parity bit
Slave address
Response time
Communications distance
Connectable devices
Termination resistor
Recommended cable
■MODBUS ® communication data
The multiplying factor of electric energy, reactive energy and periodic energy is as follows depending on the full load power
Full load power [kW] =
*1: VT primary voltage in single-phase 3-wire system is regarded as 110V.
*2: Using direct connection, replace VT primary voltage with direct voltage in calculation above.
*3: In three-phase 4-wire system, replace VT primary voltage or direct voltage with phase voltage in calculation above.
Full load power [kW]
12 or more and
120 or more and
1200 or more and
12000 or more
The multiplying factor of electric power, power demand, reactive power and apparent power is as follows depending on the
full load power
(For the full load power, refer to above.)
Full load power [kW]
less than 12
12 or more and less than 120
120 or more and less than 1200
1200 or more and
12000 or more
The multiplying factor of current and current demand is as follows depending on the primary current
Primary current [A]
less than 40
40 or more and less than 400
400 or more and less than 4000
4000 or more
The Multiplying factor of voltage and harmonic voltage is as follows depending on the primary voltage:
Caution: In three-phase 4-wire system, the Multiplying factor of VT primary voltage
and direct voltage depends on the phase voltage.
Primary voltage [V]
less than 300
300 or more
® RTU communication
RS-485 2wires half duplex
MODBUS RTU mode
Asynchronous
Multi-point bus (either directly on the trunk cable, forming a daisy-chain)
2400, 4800, 9600, 19200, 38400bps
8bit
1, 2bit
ODD,EVEN,NONE
1～255
(But 0 is impossible of authorization for a broadcast address. 248-255 is Reserve)
1s or shorter from completion of receiving query data to response transmission
Maximum 1200m
Maximum 31 devices
120Ω 1/2W
SPEV(SB)-MPC-0.2 × 1P (Mitsubishi cable industries)
Multiplying factor
α x (VT primary voltage) x (CT primary current)
1000
Multiplying factor
less than 12 ×0.01
less than 120 ×0.1
less than 1200
less than 12000 ×10
×100
Multiplying factor
×0.001
×0.01
×0.1
less than 12000
×10
Multiplying factor
×0.001
×0.01
×0.1
Multiplying factor
×0.1
Specifications
(default: 19200bps)
(default: 1bit)
(default: EVEN)
(default: 1)
α： 1 Single-phase, 2-wire
2 Single-phase, 3-wire
Three-phase, 3-wire
√3
3 Three-phase, 4-wire
×1
×1
×1
×1
(66/71)