TECHNOLOG Cello 4S, Product Manual, Page: 15 / 43

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Copyright Technolog Ltd. 2017. All rights reserved.
Information contained in this document subject to
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Sheet 15 of 43
Technolog Limited,
Ravenstor Road,
Wirksworth,
DE4 4FY,
United Kingdom T: +44 (0) 1629 823611
E: techsupport@technolog.com
www.technolog.com
DMR No.: 7504
2099PM9000 Rev. B
Standard connections - Port 3:
Two signal input (analogue and / or digital) connection
(continued)
Input = Analogue, voltage (0 to 2.5Vdc):
Input = Analogue, voltage (0 to > 2.5Vdc):
Calculation of R1 and R2 for analogue voltage inputs > 2.5Vdc:
Rule 1: R2 < 330R (i.e. 0.1% of 330K)
Rule 2: R1 = R2(2.5V / Maximum applied voltage) - R2
Example 1, for an input voltage of 0 to 18V:
Applying Rule 1, let R2 = 330R
Applying Rule 2, R1 = 330(2.5 / 18) - 330 = 2k5, 0.1% precision (2k1 is the closest precision value)
Applying these rules may take some practice.
Example 2, for an input voltage of 0 to 10V:
Applying Rule 1, let R2 = 330R
Applying Rule 2, R1 = 1k3 0.1% precision
•
•
•
•
•
•
•
•
+V
GPi2 & / or GPi3
GND (0V)
V
+
0 to 2.5Vdc
+V
GPi2 & / or GPi3
GND (0V)
V
+
R1 - precision
resistor ( ± 0.1%)
R2 -
precision
resistor
(
± 0.1%)
Internal pull-up
resistor(s) disabled
in configuration file
Internal debounce
capacitor(s) disabled
in configuration file
Internal pull-down
resistor(s) enabled
in configuration file
330k
Ω
Internal pull-up
resistor(s) disabled
in configuration file
Internal debounce
capacitor(s) disabled
in configuration file
Internal pull-down
resistor(s) enabled
in configuration file
330k
Ω
0 to > 2.5Vdc