5
Instructional Leaflet
IL66A7508H09
Effective October 2016
mMINT—Modbus translator module—
installation and use
EATON
www.eaton.com
Table 4. RS-485 baud rate switches (normal)
Baud
SW2-1
SW2-2
SW2-3
1200
X
CLOSE
CLOSE
9600
X
OPEN
CLOSE
19200
X
CLOSE
OPEN
Unique mMINT address (SW2)
The mMINT can be assigned address 247 and 248 . For the mMINT
to respond to a diagnostic query related to address 247 or 248 on
the Modbus network, move DIP switch SW2-1 to the OPEN position .
Refer to
Table 5
. Normally, this switch is in the CLOSE position .
Table 5. RS-485 baud rate switches (diagnostics)
Baud
SW2-1
SW2-2
SW2-3
Addr. 247 or 248
OPEN
X
X
Normal
CLOSE
X
X
Modbus 121 ohm termination DIP switch (SW3)
This switch should be moved to the ON position only when it is the
last unit in a chain of units or if it is a single unit .
Section 6: Network communication protocols
The lower INCOM communication network for the mMINT is
based on a master-slave protocol . The mMINT is a master on the
INCOM network .
In order to satisfy the mMINT communications needs, please see
Reference Materials:
IL17384—Part A:
INCOM Communications Standard, Eaton .
Specific product profiles are located in the other Part sections .
http://www .eaton .com, then search on 17384 .
“Modicon Modbus Protocol”
http://www .modicon .com/techpubs/toc7 .html
Overview
The contents of Modbus registers are INCOM product objects
(e .g ., I
A
—phase A current) . The mMINT ensures that unique objects
reside in identical registers independent of INCOM product .
Consequently, for all INCOM products there is a single register
map of objects . See
Table 8
or
Table 9
.
INCOM objects occupy two registers except for certain energy—
real and reactive—objects . These energy objects occupy four
registers . The mMINT can support a maximum of 122 registers
within a single Modbus transaction .
The mMINT is transparent to the Modbus master and responds
to every address of INCOM products attached to it . In its default
configured state, INCOM product addresses are Modbus network
addresses . The mMINT can be configured to route the Modbus
address to a different INCOM product address or an INCOM
sub-network product address . See Section 6 .
An upgrade has been incorporated to allow the mMINT to
communicate with Modbus masters that can only access to
register 9999 . Registers previously assigned above 9999 have
been assigned dual access, both at the original register (to provide
compatibility) and at a new register assignment below 9999 .
The format is given as low/high register numbers followed by
(low
16
/high
16
Modbus register addresses), for example:
4xxxx/4yyyyy (XXXX+1
16
/YYYY+1
16
) . See
Table 14
.
Only the RTU communications mode is recognized by the mMINT .
Function codes
The mMINT responds to a limited number of Modbus function
codes . These are function codes 03, 04, 08, and 16 (10
16
) .
Block of registers
A block of registers (from the register column of
Table 8
or
Table 9
)
can be established for each INCOM product attached to a mMINT .
Function code 16 (10
16
) is used to load the object assignments for
the block of registers . The block assignments are stored beginning at
register 41001/420481 (03E8
16
/5000
16
) .Only the first object register
address is assigned within the block of registers . For example,
although object I
A
occupies registers 404611 (1202
16
) and 404612
(1203
16
), only register address (1202
16
) is loaded into the block
of assignment registers . Verification of this block of assignment
registers can be read from the mMINT by a read function code 03
or 04 from these 41001/420481 (03E8
16
/5000
16
) registers .
Data pertaining to the objects configured in the block of assignment
registers is mapped into registers starting at 41201/420737
(04B0
16
/5100
16
) and continuing in successive order for each object
assigned . The number of objects and their placement order in this
data block of registers is dependent on the configuration of the block
of assignment registers . The total number of data block of registers
is limited to 100 .
ote:
N
An object can occupy one, two, or four registers .
The data can be obtained from the data block of registers by a read
function code 03 or 04 . The address of the starting object must be
aligned with a starting address of an object within the data block
of registers . The number of registers to obtain must align with an
ending address of an object within the data block of registers .
Register access configurations
Non-volatile register 42001/425345 (07D0
16
/6300
16
) is used to
configure the mMINT to respond to a group of data objects, of
which some objects are invalid within that group . When non-zero
(factory default value), any attempt to access a group of data objects
that contain an invalid object will result in an illegal data object
exception code 02 . See Section 6 .
When register 42001/425345 (07D0
16
/6300
16
) is set to zero, however,
the mMINT will respond to a group of objects with data contained in
the valid objects of the group along with an illegal
value, if available else 0000
16
, data contained in the invalid objects .
Non-volatile register 42002/425346 (07D1
16
/6301
16
) is used to
configure 32-bit IEEE floating point word order . When non-zero
(factory default), the floating point low order word is first in the
Modbus register space .
When register 42002/425346 (07D1
16
/6301
16
) is set to zero, however,
the floating point high order word is first in the Modbus register
space .
Non-volatile register 42002/425347 (07D1
16
/6302
16
) is used to
configure 32-bit fixed point and 64-bit energy word order . When
non-zero (factory default), the fixed point and energy low order
word is first in the Modbus register space .
When register 42003/425347 (07D2
16
/6302
16
) is set to zero, however,
the fixed point and energy high order word is first in the Modbus
register space .
Registers not containing a 32-bit or 64-bit format, such as Status and
Product ID objects, pass through registers, INCOM control registers,
and INCOM routing address configuration registers, are not effected
by the word order configuration registers .
Configuring any or all registers 42001/425345 through 42003/425347
(07D0
16
/6300
16
through 07D2
16
/6302
16
) is accomplished using a write
function code 16 (10
16
) to mMINT diagnostic address 247 or 248 .
ote:
N
mMINT SW2-1 must be properly set . See Section 5 and
Table 5
.