81 ADAM-4000 Series User ManualChapter 3 I/O Modules3.21 ADAM-4080/4080D Counter/Frequency InputModulesADAM-4080/4080D Counter/frequency input module has two 32-bit counter inputchannels (counter 0 and counter 1) with built-in programmable timer for frequencymeasurement. These cost-effective modules let you monitor counter/frequency dataas measurements are taken.Front Panel LED Indicator (ADAM-4080D only)The 5-digit LED display of the ADAM-4080D lets you monitor its counter data right atthe source. The module's LED display shows counter values as well as high-lowalarm messages when the counter exceeds its programmed limits (direct display).Another option is to display the data sent by the host computer. The module firstsends counter data to the host computer for conversion or calculation. The host com-puter then sends the data back to the ADAM- 4080D and displays on the module'sLED display (remote display).Signal Input ModeThe ADAM-4080/4080D provides separate terminals for photo isolated input andnon-isolated input to simplify the wiring. Optoisolated input provides 2500 V RMS iso-lation to protect your equipment from power surges at the ground terminal. After youmake the physical connections, program the module to identify which of its two inputterminals should be activated (isolated or non-isolated terminals).Programmable Digital FilterThe ADAM-4080/4080D module includes a unique programmable digital filter toreject noise from the input lines. You can specify separate time constant like mini-mum signal width at high level and minimum signal width at low level. This providesstable output readings.Programmable ThresholdWhen the ADAM-4080/4080D is programmed for non-isolated input, you can set ahigh and low trigger level. Like the programmable digital filter, the programmablethreshold rejects noise from the input lines and provides a stable input readingsExternal Control (Gate mode)Aside from the GND and counter terminal, each channel has a gate terminal to con-nect to an external gate signal. The gate signal (high or low) can trigger the counterfrom start or stop counting. The gate mode can be among these three options, low,high or disabled (low means that counting starts when the gate signal is low. It stopsonce the gate signal becomes high)Programmable Alarm OutputThe ADAM-4080 module provides a configurable alarm for each counter. The ADAM-4080D provides high and low alarm functions for counter 0. When the counterreaches an alarm limit, it will trigger the built-in digital output of machine ON/OFFcontrol. The alarm limits may be downloaded into the module's EEPROM by the hostcomputer. The initial count value of ADAM-4080 module's counter can be configuredin any values.
