Titan Metraflow 240-020, Инструкция по эксплуатации

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©Titan Enterprises Ltd 2018 www.flowmeters.co.uk MetraflowManual_v1219
Pin Assignments:
Each of the PIN Assignments can be adjusted as either an input
or an output function. The operation to modify PIN 6, PIN 7 and
PIN 8 are identical within the software, with the exception of the
type of transistor pulse output. PIN 6 and PIN 8 are both NPN,
whilst PIN 7 is a PNP type.
The options for each PIN (or wire colour), are:

Not Used

Input
or

Output
Not used: The assigned PIN / WIRE is unused.
Input: Select this to use the PIN assigned as a TTL digital input for remote control, either for Resetting
the Total Count or Resetting an Alarm.
When using electrical inputs for PIN 6 Yellow and PIN 8 Black, in input mode, the NPN (NFET) open
drain output is disabled, and the input pin responds to an external input voltage which may be in the
range of 0V to 30V. The logic threshold is at 2V so this input can be driven directly from a logic signal
at TTL levels or CMOS at 3.3V or 5.0V levels. Alternatively, if this input is provided by a switch, then an
example circuit is given below:
PIN 7: In input mode, the PNP (PFET) open drain output is disabled and the input PIN responds to an
external input voltage which may be in the range of 0V to 30V. The logic threshold is at 2V so this input
can be driven directly from a logic signal at TTL levels or CMOS at 3.3V or 5.0V levels.
Warning: because of the potential for conflict should the PNP output be activated accidentally, Titan
Enterprises Ltd recommend a series resistor and Zener be fitted to safeguard any connected circuitry
operating at logic levels. Alternatively, if this input is provided by a switch, then an example circuit is
given below: