Bay Technical Associates V80 PDI-2, V79 PDI-1 owner manual

The PDI module can observe, record, and report when an event happened, how long the event lasted, and how many events occurred for each individual channel. The initial occurrence of an event will set the event latch bit and store the associated time in the latch buffer. You may read the state of the initial event and the time it was recorded (if time tagging is enabled) by issuing the RL or RR commands.

Each occurrence of an event starts the duration counter and increments the event counter. The duration counter measures event duration time in milliseconds with a maximum time of 65,535 stored. You may read the duration of the last recorded event by issuing the RD command.

NOTE: Duration measurements are not de-bounced. If the input circuit cycles between active and inactive before settling, only the settled value is reported. Therefore, if a PDI module is connected to a relay or switch that has "dirty" contacts, the total measurement will be less than the actual activation duration of the circuit by the amount of time spent settling.

The event counter reflects the total number of events that have occurred since the event counter was last cleared using the CC or RO command. You may read the current event counter value by sending the RC or RO command. The event counter will trigger on the rising edge of an event when LO to HI Latch Polarity is selected or on the falling edge of an event when HI to LO Latch Polarity is selected. Examples of using the event counter would include counting items moving on a conveyor belt and process control where a pre-determined number of events must take place before a defined action may take place.

NOTE: An event must have a duration greater than one millisecond plus the current debounce delay time to increment the event counter.

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