AB 1771-VHSC Very High-speed Counter Module

AB 1771-VHSC Very High-speed Counter Module 

Preparation before installation:

Static protection: touch a grounded object when handling the module, wear a wrist strap, avoid touching the backplane connectors and internal circuitry components, and place in a static-shielding bag when not in use.

Directive Compliance: CE-marked, compliant with EU EMC and Low Voltage Directives and meets relevant standards.

Power Calculation: The module draws power from the 1771 I/O chassis backplane at a maximum current of 650mA (3.25W), 

which is required to calculate the total power in the chassis to prevent overloading.

Installation Procedure:

Jumper Setting: Each input channel has jumpers for filter/high speed operation, +5V or + 12 - 24V operation, 6 in total, which can be set independently. 

High-speed mode is suitable for encoders and other devices, and filter mode is used for electromechanical switch inputs (frequencies greater than 100Hz are not detected).

Module Installation: It can be installed in other slots except the leftmost slot, and different addressing modes have different requirements for module groups. 

The keyed strips are mounted on the backplane between 24 - 26, 28 - 30. To install, disconnect power, insert and secure the module, 

and connect the 1771-WN wiring arm.

Wiring Connections: Disconnect power before connecting I/O devices, shield sensor cables and ground only at the chassis end.

Grounding: Using Belden 9182 cable, follow the steps for cable handling and grounding, 

taking care to install a washer and nut when connecting the grounding conductor.

Module Configuration:

Operating modes: 6 modes: Counter mode, Encoder X1 mode, Encoder X4 mode, Cycle/Rate mode, Rate/Measurement mode, Continuous/Rate mode. 

For example, the counter mode is used to read pulses from up to 4 devices such as encoders; the encoder mode is used to process orthogonal pulses.

Gate/Reset Inputs and Stored Counts: Gate/Reset inputs can scale pulses, there are 4 stored counting modes that can be triggered on rising or falling edges, and stored counts can be updated by related events in specific modes.

Output Settings: Outputs can be connected to any counter input, have on and off presets, and represent frequency values in Rate Measurement mode (up to 500,000Hz).

Status and diagnostics:

Data Acquisition: The PLC processor acquires the module status and input data through the BTR instruction, which transfers up to 26 words and returns 18 words when the programmed BTR is zero.

Troubleshooting: The module returns diagnostic information in word 1 of the BTR file, including power supply, data update, and error codes. The status indicator can indicate the working status of the module, such as ACTIVE light indicates that the module receives power and operates normally, while FAULT light indicates that the module needs to be investigated according to the steps.

Specification

Electrical Performance Parameters: The maximum input frequency of the module varies depending on the mode of operation, up to 1MHz in counter mode (single channel), 250kHz in encoder mode (2-channel quadrature), 500kHz in cycle/rate, rate/measurement, and continuity/rate modes, and 100Hz in filtering mode for processing electromechanical switching inputs. Input voltages of 5V or 12 - 24V are supported and can be selected by the user according to actual requirements. Outputs are available from 5 - 24V (customer supplied) with output currents of 2A per channel and all outputs can be switched on simultaneously without derating. Output control is flexible, any number of outputs can be assigned to any of the 4 counter channels, and each output also has an ‘on’ preset and an ‘off’ preset respectively.

Environmental Adaptation Parameters: In terms of operating temperature, the module has an operating temperature range of 0 - 60°C (32 - 140°F), a storage temperature range of - 40 - 85°C (- 40 - 185°F), and a relative humidity requirement of 5 - 95% (non-condensing). These parameters define the environmental conditions under which the module can work stably. Users should ensure that the ambient temperature and humidity are within the specified range when using the module in order to avoid any degradation of performance or failure of the module due to environmental factors.

Other Parameters: The module occupies one slot in the 1771 Series A or B I/O chassis and has a programmable maximum count value of 0 - 999,999. The BTW processing time is 5.5ms in the worst case (binary and with configuration changes) and 1.5 - 2.9ms typical. The electrical isolation of the module is good, with 1500V between inputs and backplane, outputs and backplane, and 300V between isolated channels. in addition, the module is certified, e.g. with CE marking, in compliance with EU directives, and with CSA certification for use in Class I Division 2, Groups A, B, C, D, or in non-hazardous locations.