Page 6
.
Effective.June.2007
RS-485 PONI
66A2070 Rev. B
Register Access Configurations
Any attempt to access a group of data objects which contain
an invalid object will result in an illegal data object exception
code.02 .
See the
Exception Codes
section for more information. The
floating point, fixed point and energy low order words are first
in the Modbus register space.
Register 424577 (6000
16
)
Register 424578 (6001
16
)
nn = Number of Response
Msgs from
INCOM Product
INCOM Msg Byte0
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
INCOM Msg Byte1
INCOM Msg Byte2
0 = Reserved
0 = Data Msg / 1 = Control Msg
INCOM Msg Control Byte
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Figure 11. Pass-Through to INCOM Product
Query Data Format
Energy Format
Energy objects occupy four (4) registers – register 3 through
register 0. Register 3 is the high order register and register 0
is the low order register. These registers do not support IEEE
floating point format.
Register 3 high byte contains a value corresponding
to Engineering Units (power of 0 signed exponent).
Register 3 low byte contains a Mantissa Multiplier value
(power of 2 signed exponent). Register 2 through register
0 contain a 48-bit unsigned energy mantissa in units of
watt-hours. The data format of these registers is provided in
Figure 4 on Page 8.
Energy =
.
....2
Mantissa.Multiplier
x (48 bit unsigned energy value) x 0
Engineering Units
Exception Codes
Under certain circumstances, the RS-485 PONI will return an
exception.code .
•
If the function in the query is not supported by the RS-485
PONI, exception code 0 is returned in the response.
•
If the data (object) register is illegal, exception code 02 is
returned in the response.
•
If the data value in the query is illegal, exception code 03
is.returned .
•
If the slave INCOM product fails (usually a timeout),
exception.code.04.is.returned .
•
In certain circumstances, an exception code 05 (ACK) is
returned .
•
If the RS-485 PONI cannot perform the requested
.
function, exception code 07 (NACK) is returned.
•
If only a partial register is used in the query, exception
code.84.is.returned .
INCOM Protocols
•
IL 17384 – Part A
.
IMPACC Communications Standard
•
IL 17384 – Part B
.
Metering Products
•
IL 17384 – Part D
.
Motor Protection and Control
•
IL 17384 – Part F
.
Transfer Switches and //0 Devices
Supported Diagnostic Sub-Functions
It is possible to obtain diagnostics from the RS-485 PONI or
an attached INCOM product using function code 08. Refer to
Table.2 .
Troubleshooting
The most common issues experienced with the installation
of an RS-485 PONI module are addressed as follows.
If you have any questions or need further information or
instructions, contact your local representative or the Power
Quality Technial Support Center at -800-809-2772 or e-mail
pqsupport@eaton .com .
•
Status LED is not flashing.
o Verify that the 9-pin connector is plugged in.
•
Modbus Rx LED is flashing, but the RS-485 PONI does
not.respond.to.master.command.requests .
o Verify that the data transfer rate is correctly set using
baud rate switches (AO and Al).
o Verify that the communication cable is connected
correctly from the master to the Modbus slave device.
o Verify that the Network is terminated properly.
