The model 621-0008 Pulse Input Module (PIM) is a special function I/O module that counts digital pulses up to a frequency of 100k Hz. Pulses can come from any device with a pulse output such as proximity switch or flow meter. A 16-bit up counter is associated with each input. The counter, which can be read or reset by the processor, has a maximum count capacity of 65,535. There are 3-voltage range selections for each input, 5V with a 4.5 to 9 volt range, 24 V with a 10 to 32 volt range, and 48 V with a 32 to 60 volt range.
The total range of inputs is 5 to 60 Vdc.