ABB DP820 3BSE013228R1 Pulse Counter Modules

The ABB DP820 3BSE013228R1, also cataloged as the DP820 Pulse Counter Module, operates as a dedicated hardware component for high-speed pulse processing and frequency measurement within ABB S800 I/O platforms. The module interfaces with 24 VDC field signals across two individually isolated input channels, evaluating pulse counts, frequency rates, and directional inputs to execute digital signal acquisition for the controller system.

Hardware Specifications

Backplane Bus Communication Velocity and Signal Decoupling

The ABB DP820 module interfaces with the local S000 Modulebus structure to transmit high-speed counting parameters while maintaining backplane bus communication velocity across the I/O cluster. Internal logic circuits convert incoming 24 VDC pulse trains into digital values without imposing extra current load on the +24 V Modulebus line (0 mA consumption at +24 V). Channel-to-channel galvanic isolation rated at 500 VAC suppresses ground loops and cross-talk noise, maintaining signal integrity and deterministic update intervals back to the main CPU controller.

Frequently Asked Questions

Q: What is the power drain on the Modulebus backplane for the DP820 module?

A: The module draws 120 mA from the +5 VDC Modulebus logic supply and 0 mA from the +24 VDC Modulebus supply.

Q: Is channel-to-channel isolation supported on the DP820 input channels?

A: Yes, both input channels are individually isolated from each other and from the internal module common circuit, with a rated dielectric test voltage of 500 VAC.

Q: What is the maximum recommended cable distance for connecting field sensors to the DP820?

A: The maximum field cable length between the field pulse sensor and the Module Termination Unit (MTU) interface is 200 meters (218 yards).

Field Installation Guidelines

1. Module Insertion and MTU Coupling: Align the DP820 module with the guide slots of the compatible S800 Module Termination Unit (MTU). Push the module firmly onto the backplane connector until the mechanical locking latches engage fully.
2. Field Cable Routing and Distance Limits: Connect 24 VDC pulse inputs using shielded twisted-pair cables. Limit field cable runs to a maximum length of 200 meters. Route input wiring separately from high-voltage AC conductors and motor leads to avoid induced electrical noise.
3. Shield Grounding Practices: Connect field cable shields directly to the ground busbar on the MTU terminal block or enclosure earth bar using low-impedance ground clamps. Maintain ground continuity across all field junction boxes.
4. Diagnostic LED Inspection: Upon applying system power, verify that the front status LEDs indicate normal operation. Channel status indicators (PX, UP, ST, DI, SY, DO, TP) display active field signal conditions and power status per channel.