Functional diagram of the device is shown in Figure.

The device has four independent digital inputs for external control signals. To the inputs can be connected:

• switching devices (buttons, switches, reed switches, relays, etc.);

• sensors with output n-p-n-transistor with an open collector;

• sensors with output p-n-p-transistor.

The levels of the input signals are converted and processed in the matching unit and then sent to the digital signal processing unit that performs:

• reassignment of inputs in accordance with the selected counting mode (see section);

• filtering of input signals (see section);

• counting incoming pulses on the device inputs;

• convertion of the value from the counter into real physical value;

• comparing signal value to the setpoint before displaying;

• generation of signals for controlling the outputs according to a specified algorithm.

Control unit includes buttons for entering parameters of the device.

Display unit displays the measurement results or operating parameters on the indicators and shows the counter status using LEDs.

Secondary power supply converts the incoming voltage for all units of the device, depending on the version (with AC or DC power supply), and generates a signal indicating the loss of supply voltage.

The device can be connected with PC using RS-485 and USB interfaces that allow to set and edit the device configuration, monitor its current status and indications.

Elements of indication and control are located on the front panel of the device (see Figures and):

• two seven-segment six-digit digital indicators, red and green – see Table;
• six/eight LEDs (depending on the construction type) – see Table;
• four/five buttons (depending on the construction type) – see Table.

All elements are placed on two (in housings Щ1 and Н) or on three printed circuit boards (in housing Щ2).

LEDs assignment

LED	Status	Description
	lights	Key lock is on
	lights	Number of setpoint (1 or 2) that is currently displayed on the lower indicator
	lights	Direct counting
	extinguished (off)	Reverse counting
	lights	Сurrently enabled output
*	lights	Input Reset is enabled
*	lights	Input Lock is enabled

Notice

* LEDs and are not available on the housing Щ2.

Buttons assignment

Button	Operating mode of the device	Functions
	Operation	Resetting (similar to incoming "Reset" signal on the device input)
	Setup	Return previous (non-changed) value of the parameter during editing
	Operation	Change the values of setpoints
	Setup	Enter and exit the settings group Enter the parameter editing mode and exit Save the new parameter value in non-volatile memory of the device
Pressing at the same time buttons and and holding them for 2 sec opens access to configuration setup (PC-interface parameters).
	Operation	Select the digit to edit when changing the parameter value or entering the password (used with the buttons and )
	Setup
*	Operation	Change the values of setpoints
	Setup	View parameter values and edit them,enter a password

Notice

* The button is not available on the housing Щ2.

During operation, the device counts the number of incoming pulses at its counting input, compares it with setpoint, converts this quantity into a physical value, and displays the value on the indicator. Device can operate in following modes of counting:

• count-up;

• count-down;

• command;

• individual;

• reversing;

• quadrature.

During operation the counter interprets different types of signals. On the device input first incoming pulse is considered as Start signal for counting. Counting stops when the Stop signal (next pulse) comes.

If there is an active "Reset" signal, the number of counted pulses is reset (counting continues from 0).

Block prevents the transmission of the counting pulses to the device input. While this signal is active, counting is blocked.

Danger

The setpoint is specified with the same accuracy as for counting physical values.. The multiplier can be set from 0.00001 to 99999. The conversion of counting results (result of multiplying) will be rounded up.

Read more about each of the counting modes, see section.

The counter also filters the input signals with two filters. The first one filters the signal on the counting input by pulse duration (from 1 to 50,000 Hz), the second filters signal on the control inputs of the device (from 1 to 999999 microseconds).