Simex SPT-86L, Руководство пользователя

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User manual for RTD,TC,mV/4-20mA converter module SPT-86L
7. CURRENT OUTPUT VALUE CALCULATION
Output current value may be calculated by the equation (described on page 9):
I
out
=
W
−
"OutLow"
"OutHigh"
−
"OutLow"
×
16 mA

4 mA
where W means the measurement result.
Example 1: Current output value calculation
Let the current output parameters be:
”
OutMode ” = control according to measurement result,
”
OutLow
” = 100, ”
OutHigh
” = 200, ”
OutLoRange
” = 5.0, ”
OutHiRange
” = 5.0.
Parameters ”
OutLoRange
” and ”
OutHiRange
” define working range of current output to
3,8 ÷ 21 mA. Output current will be calculated for three measurement values:
a) W = 175
According to formula from page 9:
I
out
= (175-100) / (200-100) × 16 mA + 4 mA = 0.75 ·16 + 4 = 16 mA
Calculated I
out
do not exceeds the output working range (3.8 ÷ 21 mA).
b) W = 205
According to formula from page 9:
I
out
= (205-100) / (200-100) × 16 mA + 4 mA = 1.05 ·16 + 4 = 20.08 mA.
Calculated I
out
do not exceeds the output working range 3.8 ÷ 21 mA.
c) W = 300
According to formula from page 9:
I
out
= (300-100) / (200-100) × 16 mA + 4 mA = 2 ·16 + 4 = 36 mA.
Calculated I
out
exceeds the output working range (3.8 ÷ 21 mA), so current output will generate
current equal to the upper border of range defined by parameter ” OutLoRange ” and
” OutHiRange ” (that is 21 mA).
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