ABB DCS 500B, Description

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Functional Software description
6 DCS 500 Software Description
Analog Inputs
OUT+
AI2
107
OUT-
ERR
CONV MODE
HIGH VALUE
LOW VALUE
108
109
10707
10708
10709
ST5
SP
Value that corresponds to maximum
input (+10V or +20mA)
Value that corresponds to
minimum input (-10V or -20mA)
Output value
Negated output value
Error code
Selection of the Input signal type
Function Block name
P1
P3
P2 20000
-20000
1
Figure 8 Analog Input Function Block
Maximum number of analog inputs is seven. The first five chan-
nels, AITAC, AI1, AI2, AI3 and AI4, are available with the SDCS-
CON-2 or SDCS-IOB-3 boards. The last two channels, AI5 and
AI6, are connected by means of the SDCS-IOE-1 extension I/O
board.
Analog inputs are scaled with parameters:
HIGH VALUE (1XX) = value in OUT+ (XXXXX) that corresponds to
maximum input value (no10V or +20 mA).
and
LOW VALUE (1XX) = value in OUT+ (XXXXX) that corresponds to
minimum input value (normally -10V or +20 mA).
If offset balancing is needed, the value of the HIGH and LOW
VALUE has to be increased or decreased slightly.
Note. The temperature measurements are scaled internally in AI2
and AI3 (
Ω
or
°
C). The parameters HIGH VALUE and LOW VALUE
have no significance in that case.
Signal Type Selection for In-
puts The input signal type is defined by parameter CONV MODE (1XX) .
The following table shows all possible values for analog input sig-
nals in the DCS500B software.
Analog Input AIx CONV MODE-parameter selection Terminal boards & settings:
AITAC 1 = -10...+10V
-20...+20mA IOB-3: ----
IOB-3: S1:1-2 connected
2 = 4...20mA, unipolar IOB-3: S1:1-2 connected
3 = Tacho generator voltage
- 10V...+10V CON-2: 3:1-4: 90-270V
X3:2-4: 30-90V
X3:3-4: 0-30V
AI1 1 = -10...+10V
-20...+20mA CON-2; IOB-3: ----
CON-2: 500
Ω
connected X3:5-6
IOB-3: S1:3-4 connected
2 = 4...20mA, unipolar CON-2: 500
Ω
connected X3:5-6
IOB-3: S1:3-4 connected