Aie_ - Analog Input - Ethernet - Siemens 353 User Manual

Function Blocks

3.2.7 AIE_ - Analog Input - Ethernet

AIE_ function blocks use Modbus command 04 "Read
Input Registers" to enable the controller to read analog
data from other stations over the Ethernet network.
Up to 32 AIE_ blocks are available. Blocks are
assigned in sequence (e.g. AIE01, AIE02...),
controller wide, with each use.
Data can be received as a real floating-point number
and is passed to block output O1 directly or it can be
obtained as a 16-bit integer. A Floating Point number
can be formatted in one of four methods as shown in
Table 3-4 on the next page. An integer is converted to
floating point as scaled by MIN INT and MAX INT
and MINSCALE and MAXSCALE parameters. Both
Unsigned Integer (Uint) and Signed Integer (Sint)
options are available. See Table 3-5 on the next page.
When a DATA TYP is selected, range limits are
automatically entered (see Table 3-5). This ensures
that the user-entered integer values fall within the
correct range. MIN INT and MAX INT values must
be entered whenever a DATA TYP is changed.
Output OR contains the range scaling for the floating point block output O1. The OR output is a special data type
that includes the MINSCALE, MAXSCALE, DPP, and the ENGUNITS and can be connected to other blocks
having a Range (RG PTR) input. Range scaling information can be automatically obtained from the source of the
data over Ethernet if the device has the scaling information packaged with the data. This is a feature provided by
AOE function blocks from other Siemens 353 controllers. AIE blocks are connected to AOE blocks by using the
Modbus Registers from Table 3-6 below. If the automatic range scaling feature is not available, the default setting
of the RANGE parameter "MAN" should be used. In this case, range parameters are entered manually. When the
auto range feature is used, the range in the AIE block may be out of sync for several seconds if on line changes are
made to the AOE range.
The IP ADRES parameter is used to configure the IP address of the source device. The MB ADRES parameter
allows a Modbus address to be configured. When connecting to other Siemens controllers the Modbus address is
set to 1. In some cases, other devices may use a different address or when going through a Modbus TCP/IP gateway
a Modbus network may have multiple devices, each having a unique address. The REG TYP parameter allows
setting the source register as a Holding Register or an Input Register. For many Modbus devices, this setting does
not matter since the device will treat them as identical registers. The DATA TYP parameter will enable the AIE
block to acquire floating point or integer data. When floating point is selected the controller will request two
consecutive registers starting with the MB REG parameter. The UD RATE parameter configures the rate at which
the block will request data. The P2P setting will update the data at the rate set by the P2P RATE parameter in the
ETHERNET block. The Ct setting will update the data at the cycle time of the controller. The Ct parameter should
normally be used only when the analog input is the process variable in a PID control loop
Output QS indicates the quality of the received data and will go high (1) when the data is bad. This is normally
associated with failure to receive data due to a communication failure or a misconfiguration of the source.
3-14
ANALOG INPUT - ETHERNET
AIE_
ANALOG INPUT
ETHERNET
I P A D R E S IP ADdRESs
M B A D R E S MB ADdRESs
M B R E G ModBus REGister
E
R E G T Y P Modbus REGister TYPE
D A T A T Y P Modbus DATA TYPe
B Y T E O R D BYTE ORDer
Update RATE
U D R A T E
M I N I N T MINimum INTeger
M I N
A X T MAXimum INTeger
R A N G E RANGE
(S)
M I N S C A L E MINimum SCALE
M A X S C A L E MAXimum SCALE
D P P D P
ecimal
E N G U N I T S ENGineering UNITS
UM353-1B
OR Output Range
O1 Output O1
Output QS
QS
........ nnn.nnn.nnn.nnn
(192.168.0.0)
(H)
.......................... 1 - 255
(1)
(H)
................ 1 - 65535
(1)
(H)
.
InPut/Holding (InPut)
(H)
..... FP/Uint/Sint
(FP)
(H)
........................... 1/2/3/4
(4)
(S)
......................... P2P/Ct
(P2P)
(H)
............ (see table 2)
(*)
(S)
........... (see table 2)
(*)
(S)
............................... Man/Auto
(M)
........................ Real
(0.0)
(S)
....................... Real
(100.0)
(S)
P
t. osition (preferred) (S) ............ 0.0.0.0.0.0 0.00
....... 6 ASCII Char
(PRCT)
(S)
April 2012