Dryer Master AM3, Руководство по эксплуатации продукта

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Dryer Master  A M 3 Product Manual
© Dryer Master Inc. Page: 46
How Rate Scale values work:
The rate scale values determine the maximum and minimum displayed values for discharge rate.
Different systems have different indicators of speed. These values are typically set to mimic the
systems current values.
1) In voltage mode, the default setting, the Maximum output voltage is 10 volts and the Minimum
output voltage is 0 volts.
2) For Example:
Suppose we have the following application
a) The maximum displayed value = 100 and the voltage we need = 8 volts
b) The minimum displayed value = 0 and the voltage we need = 2 volts
c) For a range of 0 to 100 we have a voltage change of 2 to 8 volts or s span of (8-2=6) 6.
d) This means we have (100 / 6) = 16.67 speed units per volt
e) The minimum displayed value = 0 and the voltage is 2 volts. Therefore we will need to
subtract (2 * 16.67 = 33.34) from the 0 value.
“ Rate Scale Min ” becomes -33.34
f) The maximum display value of 100 is reached at 8 volts. Therefore at 10 volts we would
see (10 * 16.67 = 166.70)
. So the “ Rate Scale Max ” value will need to be set to (166.70 -
33.34 = 133.36)
The display will drive 4 to 20 mA into a 250 ohm load with the voltage setting.
For 0 to 100 scale and 1 to 5 volts or 4 to 20 Ma output into a
250 ohm load while in default voltage
output mode:
1) Still in voltage mode the Maximum output voltage is 10 volts or 40 mA and the Minimum output
voltage is 0 volts or 0 mA.
2) For Example:
Suppose we have the following application
a) The maximum displayed value = 100 and the voltage we need = 5 volts = 20 mA
b) The minimum displayed value = 0 and the voltage we need = 1 volt = 4 mA
c) For a range of 0 to 100 we have a voltage change of 1 to 5 volts or s span of (5 – 1 = 4) 4
or a current change of 4 to 20 mA or s span of (20 – 4 = 16) 16
d) This means we have 100 / 4 = 25 speed units per volt or 100 / 16 = 6.25 speed units per
mA.
e) The minimum displayed value = 0 and the voltage is 1 volt or 4 mA. Therefore we will
need to subtract (1 * 25 = 25 if voltage or ( 4 * 6.25 = 25) from the 0 value.
“ Rate Scale
Min ” becomes -25
f) The maximum display value of 100 is reached at 5 volts or 20 mA. Therefore at 10 volts
or 40 mA we would see (10 * 25 = 250) for volts or (40 * 6.25 = 250) so
the “ Rate Scale
Max ” value will need to be set to (250 -25 =225).
See the Appendix to change the jumpers for milliamp current loop output. The same formula applies
for milliamp signals in which case the total range is 0 to 20 mA. The display will drive 0 to 20 mA into a
500 or lower ohm load.
For 0 to 100 scale and 4 to 20 Ma output into a load of any value equal too or less than 500 ohm:
3) In current mode the Maximum output current 20 mA and the Minimum output current is 0 mA.
4) For Example:
Suppose we have the following application
a) The maximum displayed value = 100 and the voltage we need = 20 mA