Gill Instruments Ltd
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MetPak/MetPak RG and MetPak Pro
Page | 61
Issue 1
Doc. No. 1723-PS-0022
October 2018
MetPak MODBUS NOTES
To work out Modbus register numbers applicable to a MetPak parameter, start out with
setting up the MetPak in ASCII mode and determining which parameters are to be output,
and the exact order that they are to be output before setting to Modbus Comms.
Refer to the Modbus output parameter table below to determine how many
registers each chosen parameter will take up.
Fill up the register table, starting at 40001, with the required output parameters in
the order in which they will be output.
Note:
After powering up the MetPak, wait 10 seconds before requesting any
measurements.
MetPak
Output Parameters
Type
No. of
Registers
Register Numbers
NODE
4 Bit Character String
2
40001-2
DIRECTION
32 Bit Floating Point Value
2
40003-4
SPEED
32 Bit Floating Point Value
2
40004-5
PRESSURE
32 Bit Floating Point Value
2
40006-7
RELATIVE HUMIDITY
32 Bit Floating Point Value
2
40008-9
TEMPERATURE
32 Bit Floating Point Value
2
40010-11
DEWPOINT
32 Bit Floating Point Value
2
40012-13
SUPPLY VOLTAGE
32 Bit Floating Point Value
2
40014-15
STATUS
32 Bit Unsigned Integer (UINT)
2
40016-17
MetPak RG
Output Parameters
Type
No. of
Registers
Register Numbers
NODE
4 Bit Character String
2
40001-2
DIRECTION
32 Bit Floating Point Value
2
40003-4
SPEED
32 Bit Floating Point Value
2
40005-6
PRESSURE
32 Bit Floating Point Value
2
40007-8
RELATIVE HUMIDITY
32 Bit Floating Point Value
2
40009-10
TEMPERATURE
32 Bit Floating Point Value
2
40011-12
DEWPOINT
32 Bit Floating Point Value
2
40013-14
DIG1
32 Bit Floating Point Value
2
40015-16
SUPPLY VOLTAGE
32 Bit Floating Point Value
2
40017-18
STATUS
32 Bit Unsigned Integer (UINT)
2
40019-20
MetPak Pro
Output Parameters
Type
No. of
Registers
Register
Numbers
NODE
4 Bit Character String
2
40001-2
DIRECTION
32 Bit Floating Point Value
2
40003-4
SPEED
32 Bit Floating Point Value
2
40005-6
PRESSURE
32 Bit Floating Point Value
2
40007-8
RELATIVE HUMIDITY
32 Bit Floating Point Value
2
40009-10
TEMPERATURE
32 Bit Floating Point Value
2
40011-12
DEWPOINT
32 Bit Floating Point Value
2
40013-14
PRT
32 Bit Floating Point Value
2
40015-16
AN1
32 Bit Floating Point Value
2
40017-18
AN2
32 Bit Floating Point Value
2
40019-20
DIG1
32 Bit Floating Point Value
2
40021-22
SUPPLY VOLTAGE
32 Bit Floating Point Value
2
40023-24
STATUS
32 Bit Unsigned Integer (UINT)
2
40025-26