GE DS3820CJ1A

Key Parameters

• Channels: 1 counter/totalizer input

• Input Type: 24 V DC (sourcing/sinking configurable)

• Maximum Input Frequency: 100 kHz (with filter disabled)

• Resolution: 32-bit counter

• Count Modes: Up/down counting, rate (frequency) measurement, totalization, batch counting, preset counting

• Input Filtering: Software-selectable 0.1–10 ms debounce

• Preset Output: One discrete output (24 V DC, 0.5 A) – activates when count reaches preset value

• Isolation: 1500 V RMS (field-to-backplane)

• Diagnostics: Per-channel LED status, over-range detection, output short-circuit protection

• Power: 24 V DC backplane power, ≤1.5 W (plus external field supply for output)

• Operating Temperature: –40°C to +70°C

Advantages

• Dedicated single-channel counter – optimized for high-integrity counting; no shared resources with other channels.

• Integrated preset output – built-in discrete output triggers alarms or control actions when count reaches a preset value; eliminates PLC logic and external relay.

• Versatile measurement modes – supports counting, rate/frequency measurement, totalization, and batch counting in one module.

• Batch counting capability – counts batches and resets automatically, ideal for packaging and production line applications.

• Adjustable input filtering – eliminates false counts from contact bounce and electrical noise.

• Hot-swappable – replace without rack power-down.

• 32-bit counter range – eliminates rollover concerns for most industrial applications.

• Compact form factor – single-channel design reduces cost for applications needing only one counter.

Applications

• Flow totalization – accumulating pulses from turbine flowmeters for liquid/gas measurement

• Production counting – piece counting on assembly lines with alarm at target quantity

• Batch processing – counting parts per batch with automatic reset and output signal

• Conveyor systems – counting packages or products with alarm at preset quantity

• Pumping stations – totalizing pump cycles or flow pulses

• Packaging machinery – counting filled containers with batch completion output

• Material handling – counting pallets or cartons with overfill alarm

Competitor Comparison

The DS3820CJ1A is the cost-optimized single-channel counter with built-in control output. Compared to the multi-channel DS3820CI2A, it offers fewer channels but adds a valuable preset output – eliminating the need for a separate PLC output module or external relay. Against competitor single-counter modules, the DS3820CJ1A provides superior versatility (batch counting, totalization, preset) and higher frequency (100 kHz vs. 50 kHz) at a comparable price. For applications requiring only one counter with an integrated alarm or control output, the DS3820CJ1A delivers the most cost-effective solution.

Selection Tips

• Choose DS3820CJ1A for single-channel counting applications that require a built-in output when a count target is reached.

• Ideal for flow totalization with alarm output, production piece counting, and batch counting with reset.

• Verify the sensor type (24 V DC, NPN/PNP) matches the DS3820CJ1A input configuration.

• Consider the preset output rating – 24 V DC, 0.5 A – sufficient for driving relays, lights, or small solenoids directly.

• Not suitable for high-speed quadrature encoders (use DS3820CI2A family) or applications needing two independent counters.

• Ensure your PLC reading cycle can keep up with the DS3820CJ1A‘s 100 kHz counting rate.

Precautions

• Preset output wiring: The output is 24 V DC, 0.5 A – do not exceed current rating. Use an external relay or contactor for higher loads.

• Output protection: The output includes short-circuit protection, but extended overload may damage the module – size loads appropriately.

• Frequency limits: Maximum 100 kHz achieved only with filtering disabled. Enable filtering only if necessary.

• Wiring: Use shielded twisted-pair cables for the input signal, especially at high frequencies. Ground shield at module end only.

• Input voltage: Do not exceed 24 V DC nominal – the DS3820CJ1A is not rated for higher voltages.

• Power sequencing: Apply backplane power before field power to avoid spurious counts or output triggers during startup.

• Count loss: At frequencies near 100 kHz, ensure the PLC reading cycle is faster than the counter update to avoid missing counts.

• Configuration: Set count mode (up/down, totalize, batch) and preset value before enabling the channel.

• Spare: Keep one spare DS3820CJ1A for critical counting loops – the integrated output makes it a single point of failure in control applications.