ALTHEN SG-IP-12E 4P Series, Manual

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5.1.1 Tare
A potential base load can be electrically suppressed by an additional resistor (-network) on the pcb, if an
expansion of the zero-point adjustment range is neither sufficient, nor desirable.
In order to do so, a combination of resistors, respectively bridges and one potentiometer has to be
soldered in. The solder-point LP-03 determines, if the tare is activated. LP-02 has to be set for positive,
or negative adding. With the potentiometer P-50 a tare of up to 10 times the actual measuring range can
be adjusted. However, the adjustment just by potentiometer is rather coarse,
thus inaccurate. In order to improve the accuracy, it is possible to narrow the
voltage range of the potentiometer down, with a voltage divider.
LP-02: + Tara LP-03: Tara aktiviert
– Tara Tara inaktiv
10 V
R38
Poti
R39
Example 1:
Measuring Range:
+ 200 kN (equals 1 V)
Tare: + 100 kN (equals 0,5 V)
Tare range: ± 50 kN (equals ± 0,25 V)
Tara lower value: + 50 kN (equals 0,25 V)
Tara upper value: + 150 kN (equals 0,75 V)
So, the poti should have an adjustment range from 0,25 to 0,75
Volts. That means, with an overall voltage of 10 Volts and a
potentiometer of 10 kOhm by default, the first series resistor (R-
39) has to be 5 kOhm and the second one (R-38) 185 kOhm.
Example 2:
Measuring Range:
+ 1000 kN (equals 1 V)
Tare: + 1000 kN (equals 1 V)
Tare range: ± 200 kN (equals ± 0,2 V)
Tara lower value: + 800 kN (equals 0,8 V)
Tara upper value: + 1200 kN (equals 1,2 V)
So, the poti should have an adjustment range from 0,8 to 1,2 Volts. That means, with an overall
voltage of 10 Volts and a potentiometer of 10 kOhm by default, the first series resistor (R-39) has
to be 20 kOhm and the second one (R-38) 220 kOhm.