Serial communications

USB-C

RS-485 communications

The drive has an RJ45 connector on the front of the control panel. This connector allows the user to set up a drive network via a wired connection. The connector contains two independent RS485 connections, one for Invertek’s Protocol and one for Modbus RTU. Both connections can be used simultaneously.

The electrical signal arrangement of the RJ45 connector is shown as follows:

	CAN-
	CAN+
	0 Volt
	RS 485- PC Connection
	RS 485+ PC Connection
	+24 Volt Remote Keypad Power Supply
	RS 485- Modbus RTU
	RS 485+ Modbus RTU

Modbus RTU Communications

Modbus Telegram Structure

The drive supports Master / Slave Modbus RTU communications, using the 03 Read Holding Registers and 06 Write Single Holding Register commands. Many Master devices treat the first Register address as Register 0; therefore, it may be necessary to convert the Register Numbers detailed by subtracting 1 to obtain the correct Register address.

The telegram structure is as follows:-

Command 03 – Read Holding Registers
Master Telegram	Length		Slave Response	Length
Slave Address	1	Byte	Slave Address	1	Byte
Function Code (03)	1	Byte	Starting Address	1	Byte
1^st Register Address	2	Bytes	1^st Register Value	2	Bytes
No. Of Registers	2	Bytes	2^nd Register Value	2	Bytes
CRC Checksum	2	Bytes	Etc...
			CRC Checksum	2	Bytes

Command 06 – Write Single Holding Register
Master Telegram	Length		Slave Response	Length
Slave Address	1	Byte	Slave Address	1	Byte
Function Code (06)	1	Byte	Function Code (06)	1	Byte
Register Address	2	Bytes	Register Address	2	Bytes
Value	2	Bytes	Register Value	2	Bytes
CRC Checksum	2	Bytes	CRC Checksum	2	Bytes

Modbus Control & Monitoring Registers

The following is a list of accessible Modbus Registers available in the drive.

Registers 1 and 2 can be used to control the drive providing that Modbus RTU is selected as the primary command source (P1-01 = rtu)
Register 4 can be used to control the acceleration and deceleration rate of the drive providing that Fieldbus Ramp Control is enabled (P2-07 = 1)
Registers 6 to 24 can be read regardless of the setting of P1-01

Register Number

Upper Byte

Lower Byte

Read

Write

Notes

Command Control Word

R/W

Command control word used to control the drive when operating with Modbus RTU.

Bit	Function when 0	Function when 1	Notes
0	Stop	Run Up
1	Stop	Run Down
2	Not Reset	Reset Command	This bit must be reset to zero once the fault has been cleared.
Bit 3-7	Reserved

Commanded Speed Reference

R/W

Speed reference sent must match the speed units which the drive has been programmed to operate in e.g. Hz, Rpm, Linear units

P4-06>0	Below Values entered: P3-08 (Sheave diameter) P3-09 (Roping Ratio) P3-10 (Gear Ratio)	P3-08 (Sheave diameter) >100	P3-08 (Sheave diameter) <100	Units	Write Values/Scaling
x	x	x	x	Hz	e.g. 50.0 = 50.0Hz
√	x	x	x	rpm	e.g. 500 = 500rpm
√	√	√	x	m/s	e.g. 0.01 = 0.01m/s
√	√	x	√	Ft/min	e.g. 0.1 = 0.1 ft/min

Commanded Torque Reference

R/W

Command Ramp times

R/W

This register specifies the drive acceleration and deceleration ramp times used when Fieldbus Ramp Control is selected (P2-07 = 1) and P1-01 is set to rtu

The input data range is from 0 to 60000 (0.00s to 600.00s)

Internal Speed Reference

Status Word

Bit	Definition	Description
0	Ready	This bit is set if no trip and no mains loss, plus hardware enabled
1	Running	This bit is set when drive is running
2	Tripped	This bit is set when drive is under trip condition
3	Standby	This bit is set when drive is in standby mode
4	Fire Mode	This bit is set if Fire mode is active
5	Reserved	Read as 0
6	Speed Set-point Reached (At Speed)	This bit is set when drive is enabled and reaches speed set point
7	Below Minimum Speed	This bit is set when drive is enabled and speed less than P8-02
8	Overload	This bit is set if motor current > P4-03
9	Mains Loss	This bit is set if mains loss condition happens
10	Heatsink > 85°C	This bit is set if drive heatsink temperature over 85°C
11	Control Board > 80°C	This bit is set if control PCB temperature over 80°C
12	Switching Frequency Reduction	This bit is set if PWM switching frequency foldback is active
13	Reverse Rotation	This bit is set when motor is in reverse rotation (negative speed)
14	Rescue Mode	This bit is set if Rescue mode is active
15	Live Toggle Bit

Output Speed

Output speed in the units that the drive is operating in. e.g. rpm, m/s

Output Current

Output current of the drive to one decimal place, e.g.105 = 10.5 Amps

Output Torque

Motor output torque level to one decimal place, e.g. 474 = 47.4 %

Output Power

Output power of the drive to two decimal places, e.g.1100 = 11.00 kW

Digital Input Status

Represents the status of the drive inputs as per below

Bit	8	7	6	5	3	2	1	0
	Digital Input 8	Digital Input 7	Digital Input 6	Digital Input 5	Digital Input 4	Digital Input 3	Digital Input 2	Digital Input 1

Drive Rating ID

TBC how it is displayed

Drive Power Rating

Drive Voltage Rating

I/O Firmware

Power Firmware

Drive Type Code

Active Error Code

Displays the current Error code.

Refer to section 22.1 for a list of fault codes and diagnostic information

Analog 1 Level

Analog Input 1 Applied Signal level in % to one decimal place, e.g. 1000 = 100.0%

Analog 2 Level

Analog Input 2 Applied Signal level in % to one decimal place, e.g. 1000 = 100.0%

Pre Ramp Speed Reference

Internal drive frequency setpoint

DC bus voltage

Measured DC Bus Voltage in Volts

Drive temperature

Measured Heatsink Temperature in °C

Serial 4

The values shown in these 4 registers can be merged to read the drive serial number as shown below

Register	28	27	26	25
Value	1234	1234	1234

65940603029

Serial 3

Serial 2

Serial 1

Digital Output 1-3 state

Energy Usage (kWh)

Energy Usage (MWh)

Run Time Since Last Enable

H:M

Run Time Last Enable

Control Board Temperature

Modbus Parameter Access

All User Adjustable parameters are accessible by Modbus, except those that would directly affect the Modbus communications, e.g.

P2-01 Modbus Slave Address
P2-02 Modbus RTU Baud Rate
P2-03 Modbus RTU Data Format

All parameter values can be read from the drive and written to, depending on the operating mode of the drive – some parameters cannot be changed whilst the drive is enabled for example.

When accessing a drive parameter via Modbus, the Register number for the parameter is the same as the parameter number,

E.g. Parameter P1-01 = Modbus Register 101.

Modbus RTU supports sixteen bit integer values, hence where a decimal point is used in the drive parameter, the register value will be multiplied by a factor of ten,

E.g. Read Value of P1-01 = 500, therefore this is 50.0Hz.

Modbus Parameter Access of group 0 parameters.

Group 0 parameters can be accessed as per the following examples :

To read the value in parameter P0-32 (Back EMF measured value), read register 10032.

To read the value in parameter P0-38 (Last Trip 1- Newest Trip), read register 10038.

To read the value in parameter P0-38-1 (Last Trip 2), read register 11000???

In this section:

Elevator Core Reference Guide