GE AF-650 GP Series, Design And Installation Manual

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9.2.5 How to Access Parameters
9.2.5.1 Parameter Handling
The PNU (Parameter Number) is translated from the
register address contained in the Modbus read or write
message. The parameter number is translated to Modbus
as (10 x parameter number) DECIMAL.
All parameters are named with one or two letters, a "-" and
a number for example, F-07. To access parameters, use
Table 9.12 because letters cannot be addressed.
Example: F-07=7, E-01=101, DR-53=1253.
Letter Number
F 0
E 1
C 2
P 3
H 4
K 5
AN 6
B 7
O 8
PB 9
SP 10
XC 11
DR 12
LG 13
CL 14
ID 15
AP 16
T 17
FB 18
PC 19
AO 20
BP 21
DN 22
PI 23
LC 24
EC 25
RS 26
BN 27
LN 28
EN 29
CB 30
CA 31
CD 32
Table 9.12
9.2.5.2 Storage of Data
The Coil 65 decimal determines whether data written to
the adjustable frequency drive are stored in EEPROM and
RAM (coil 65=1) or only in RAM (coil 65=0).
9.2.5.3 IND
The array index is set in Holding Register 9 and used when
accessing array parameters.
9.2.5.4 Text Blocks
Parameters stored as text strings are accessed in the same
way as the other parameters. The maximum text block size
is 20 characters. If a read request for a parameter is for
more characters than the parameter stores, the response is
truncated. If the read request for a parameter is for fewer
characters than the parameter stores, the response is
padded with spaces.
9.2.5.5 Conversion Factor
The different attributes for each parameter can be seen in
the section on factory settings. Since a parameter value
can only be transferred as a whole number, a conversion
factor must be used to transfer decimals.
Conversion index Conversion factor
100
75
74
67
6 1,000,000
5 100,000
4 10,000
3 1,000
2 100
1 10
0 1
-1 0.1
-2 0.01
-3 0.001
-4 0.0001
-5 0.00001
-6 0.000001
-7 0.0000001
Table 9.13 Conversion Table
RS-485 Installation and Set... AF-650 GP
TM
Design and Installation Guide
9-6 DET-767A
9 9