inputs must be using lo-res modes.
Qualifier 1 – Enter the configuration qualifier value, if applicable, for the selected
configuration. Qualifiers are required only in the following modes:
4-20mA modes: The qualifier is the resistance in ohms of the dropping resistor used to
convert the current to voltage. An external resistor must be provided, connected
between the A/UI input and ground/common. The resistor needs to be 1/2 watt (2
watt to withstand 24V power), and is left external simply because miswiring the
4-20mA sensor can easily apply 24V power directly to the input and cause the
dropping resistor to heat up and possibly fail. The external resistor is simple to
replace, whereas an internal resistor on a circuit board would be more trouble to
replace.
Discrete and Dry Contact modes: The qualifier is a threshold between 1% and 99% at
which the input should trip from off to on or vice versa. Although the A/UI inputs are
specified as 0-10V inputs, they will actually measure up to 11.4V accurately in hi-res
mode, and up to 15.0V in lo-res mode. Therefore, since discrete inputs are sampled as
lo-res analog values and compared to a threshold, the qualifier here is a percentage of
15V for the trip point. A value of 50% will mean a threshold of around 7.5V.
Pulse, Low Speed mode: Because low speed pulse input is really a different
interpretation of discrete input, a threshold setting is required for pulse sensing. The
same threshold as used for discrete input applies here. Without any threshold (or with
value of zero), no pulse counting will occur.
Position Pot: Position is simply a different interpretation of resistance measurement.
The value resulting from position pot measurement will be a percentage from 0% to
100%, but this percentage will be a ratio based on the resistance value in ohms
provided as the qualifier.
Qualifier 2 – Enter a second configuration qualifier value if instructed to do so. This
qualifier is reserved for future use.
Physical Point – The physical I/O point assigned to the displayed object is indicated
here.
8. Object Map Page
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