Shinko DCL-33A - Converter Setting Example; Example Input;Output Conditions; Calculation of Scaling Values; Conversion Diagram

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6.2 Converter Setting Example
[Other Inputs except 4 to 20 mA DC]
Input, output conditions
Input: 6 to 14 mA DC (Indication: 30.0 to 130.0)
Output: 4 to 20 mA DC
Setting method
(1) Calculating Scaling high and low limit value of 4 to 20 mA DC
Indication value per mA DC: (130.0 – 30.0) ÷ (14 – 6) = 100 ÷ 8 = 12.5
Scaling high limit value: 130.0 + (20 – 14) x 12.5 = 205.0
Scaling low limit value: 30.0 – (6 – 4) x 12.5 = 5.0
(2) Calculating OUT proportional band of 6 to 14 mA DC
OUT proportional band (P) = {(14 – 6) ÷ (20 – 4)} x 100 = 0.5 x 100 = 50 (%)
(3) Calculating SV so that output can become 4 mA DC from 6 mA DC input (Parallel shift
setting)
SV = {(6 – 4) x 12.5} + 5.0 (Scaling low limit) = 30.0
Input, output and indication
(Fig. 6.2-1)
P = 50%
Output
20 mA
4 mA
4 mA 6 mA
20 mA
14 mAInput
Indication
5.0 30.0
205.0130.0
SV
P = 50%
12 mA
105.0
(2)
(3)
: Input and output when P=100%, SV=5.0
: Input and output when P=50%, SV=5.0
: Input and output when P=50%, SV=30.0