Fieldbus Scale - IMO HD2 IP Series Instruction Manual

HD2 IP55 High-ingress Protection Series Inverter
running and stop operations as examples, you need to set "Running command channel"
(P00.01) to "Communication" and set "Communication running command channel" (P00.02) to
the Modbus communication channel. For another example, when modifying "PID setting", you
need to set "PID reference source" (P09.00) to Modbus communication.
The following table describes the encoding rules of device codes (corresponding to the
identification code 2103H of the inverter).
8 MSBs
01

9.4.6 Fieldbus scale

In practical applications, communication data is represented in the hexadecimal form, but
hexadecimal values cannot represent decimals. For example, 50.12 Hz cannot be represented
in the hexadecimal form. In such cases, we can multiply 50.12 by 100 to obtain an integer 5012,
and then 50.12 can be represented as 1394H (5012 in the decimal form) in the hexadecimal
form.
In the process of multiplying a non-integer by a multiple to obtain an integer, the multiple is
referred to as a fieldbus scale.
The fieldbus scale depends on the number of decimals in the value specified in "Description"
or "Default value". If there are n decimals in the value, the fieldbus scale m is the power n of 10.
Take the following table as an example, m is 10.
Function
code
P01.20 Wake-up-from-sleep delay 0.0–3600.0s (valid when P01.19 is 2)
P01.21
The value specified in "Description" or "Default value" contains one decimal, so the fieldbus
scale is 10. If the value received by the upper computer is 50, the value of "Wake-up-from-sleep
delay" of the inverter is 5.0 (5.0=50/10).
To set the "Wake-up-from-sleep delay" to 5.0s through Modbus communication, you need first
to multiply 5.0 by 10 according to the scale to obtain an integer 50, that is, 32H in the
hexadecimal form, and then transmit the following write command:
inver
ter
address
Meaning
GD
Name
Restart after power cut
01
Parameter
Write
command
8 LSBs
0x08
0x09
0x0a
0xa0
0: Restart is disabled
1: Restart is enabled
06
Parameter
address data
-276
Meaning
GD35 vector inverter
GD35-H1 vector
inverter
GD300 vector
inverter
HD2IP vector inverter
Description
01 14 00 32
CRC
Default
value
0.0s
0
49 E7