PCI-6624 8-Channel Isolated 48 V Counter/Timer Device
Земля PCI-6624 is an industrial counter/timer device designed for automotive, aerospace, manufacturing, motion-control and automated test applications. It provides eight 32-bit counter/timers with channel-to-channel isolated field interfaces supporting signals up to 48 VDC.
The device includes 26 isolated inputs and eight isolated sinking outputs. Each counter has dedicated source, gate and auxiliary inputs, while two additional programmable function inputs support flexible triggering and signal routing.
Unlike TTL-only counter boards, the PCI-6624 can connect to higher-voltage industrial sensors, encoders and control equipment without requiring separate TTL-level interfaces in many applications. It also includes input overvoltage protection, output short-circuit protection and automatic output recovery.
Key Features of the PCI-6624
- Eight independent 32-bit up/down counter/timers
- 26 channel-to-channel isolated input channels
- Eight channel-to-channel isolated sinking outputs
- Up to 48 VDC input and output operation
- 400 kHz maximum isolated input frequency
- 400 kHz maximum isolated output frequency
- 20 MHz maximum internal counter source frequency
- 100 kHz and 20 MHz internal timebases
- 60 VDC channel-to-channel isolation
- 60 VDC channel-to-ground isolation
- 100 mA maximum switching current per output
- 600 mA maximum output inrush current
- Reverse-voltage and overvoltage protection
- Output short-circuit protection with automatic recovery
- Up to three simultaneous DMA transfers
- Seven PCI RTSI trigger lines
- 100-pin female SCSI-II front connector
- NI-DAQmx software support
PCI-6624 Technical Specifications
| Product Model | PCI-6624 |
|---|---|
| Part Number | 778834-01 |
| Product Type | Industrial isolated counter/timer device |
| Number of Counter/Timers | 8 |
| Counter Resolution | 32 bits |
| Counter Operation | Up/down counting |
| Maximum Counter Value | 4,294,967,295 |
| Internal Timebases | 100 kHz and 20 MHz |
| Base-Clock Accuracy | 50 ppm, ±0.005%, over temperature |
| Maximum Internal Counter Source Frequency | 20 MHz |
| Isolated Input Channels | 26, consisting of three per counter plus two additional PFI inputs |
| Isolated Input Type | Driven reference to supply or ground, two terminals per input |
| Input Voltage Range | Up to 48 VDC |
| Guaranteed Input ON Voltage | 4.1 V |
| Guaranteed Input OFF Voltage | 0.8 V |
| Typical Input ON Voltage | 2.5 V |
| Maximum Isolated Input Frequency | 400 kHz |
| Minimum Input Pulse Width | 1 мкс |
| Typical LOW-to-HIGH Input Delay | 350 ns with a 5 V input signal |
| Typical HIGH-to-LOW Input Delay | 220 ns with a 5 V input signal |
| Isolated Output Channels | 8 |
| Тип вывода | Sinking, low-side switch |
| Output Field-Power Requirement | 5 VDC to 48 VDC |
| Output Load-Voltage Range | 5 VDC to 48 VDC |
| Maximum Output Current | 100 mA per channel |
| Maximum Output Inrush Current | 600 mA per channel |
| Maximum Isolated Output Frequency | 400 kHz |
| Minimum Output Pulse Width | 1 мкс |
| Typical Output Turn-On Time | 500 ns with a 5 V, 100 Ω load |
| Typical Output Turn-Off Time | 150 ns with a 5 V, 100 Ω load |
| Data Transfer | DMA for up to three channels plus interrupt transfers |
| PCI RTSI Trigger Lines | 7 trigger lines plus one RTSI clock |
| Изоляция | 60 VDC channel-to-channel and channel-to-ground, Measurement Category I |
| Front Connector | 100-pin female SCSI-II type |
| Шинный интерфейс | Conventional PCI |
| Power Requirement | 0.75 A from +5 V and 0.15 A from +3.3 V |
| Dimensions | 17.5 cm × 10.7 cm |
| Operating Temperature | 0°C to 55°C |
| Поддержка программного обеспечения | НИ-DAQmx |
PCI-6624 Part Number and Accessories
| Item | Part Number | Описание |
|---|---|---|
| PCI-6624 | 778834-01 | Eight-channel, channel-isolated 48 V industrial counter/timer device |
| SH100M-100M Flex Cable | 185095-01 | 1 m shielded 100-pin female-to-male flexible I/O cable |
| SH100M-100M Flex Cable | 185095-02 | 2 m shielded 100-pin female-to-male flexible I/O cable |
| SCB-100A Connector Block | 785024-01 | Shielded 100-pin screw-terminal connector block |
| R1005050 Cable | 182762-01 | 1 m unshielded cable converting one 100-pin connection to two 50-pin connectors |
| R1005050 Cable | 182762-02 | 2 m unshielded cable converting one 100-pin connection to two 50-pin connectors |
| CB-50 Connector Block | 776164-90 | 50-pin screw-terminal connector block |
| CB-50LP Connector Block | 777101-01 | Low-cost 50-pin connector block |
The recommended connection uses an SH100M-100M Flex shielded cable and an SCB-100A connector block. When an R1005050 cable is used, two compatible 50-pin connector blocks are required to access all PCI-6624 signals.
Eight Industrial Counter/Timer Channels
The PCI-6624 contains eight independent 32-bit up/down counter/timers. Each counter provides isolated source, gate and auxiliary inputs together with an isolated sinking output.
This architecture allows separate field references to be used for different counters. It is useful when sensors and actuators are distributed across several electrical subsystems that do not share a common ground.
The eight counters can perform different operations concurrently. For example, several counters can monitor encoders while others measure frequency, count events or generate control pulses.
26 Channel-Isolated Inputs
The device provides 26 isolated input channels. Three inputs are associated with each of the eight counters, producing 24 counter inputs, while two additional programmable function inputs support other routing and triggering requirements.
Each input uses two terminals and can be referenced toward either the field supply or field ground. This arrangement supports a wider range of industrial sensor and signal configurations than a single-ended TTL counter input.
48 VDC Industrial Input Compatibility
The isolated inputs accept signals up to 48 VDC, making the PCI-6624 suitable for common 5 V, 12 V, 24 V and 48 V control systems when correctly wired.
A guaranteed ON state requires at least 4.1 V, while a signal at or below 0.8 V is guaranteed to be OFF. Voltages between the guaranteed thresholds should not be used as normal logic levels.
Although the inputs support industrial voltages, the device is intended for Measurement Category I circuits and must not be connected directly to mains distribution circuits.
400 kHz Isolated Input Frequency
Each isolated field input supports signal frequencies up to 400 kHz with a minimum pulse width of 1 µs. This enables the device to monitor industrial encoders, flow sensors, proximity sensors and other pulse-generating equipment operating beyond typical mechanical-switch speeds.
The 400 kHz rating applies to the isolated field interface. Internally, the counter/timer circuitry provides a maximum source frequency of 20 MHz when an appropriate signal is routed through supported internal paths.
Eight Isolated Sinking Outputs
The PCI-6624 includes eight isolated sinking outputs. Each output acts as a low-side switch and completes the load circuit by connecting the output toward its field-supply return when activated.
The load and external supply must be wired according to the official pinout. An external field supply from 5 VDC to 48 VDC is required for output operation because the PCI bus does not power the connected industrial load.
100 mA Output Switching
Each isolated output can switch up to 100 mA. The outputs can therefore interface with compatible indicators, small relay coils and electronic control inputs without requiring a separate low-side driver.
Loads requiring more than 100 mA continuous current should be controlled through an external relay, solid-state relay or power driver. The external interface must be selected for the load voltage, current, switching frequency and inrush characteristics.
600 mA Inrush Capability
Each output supports a maximum inrush current of 600 mA. This helps accommodate the short starting-current surge produced by some capacitive loads, lamps and relay coils.
Inrush capability is not a continuous-current rating. The connected load must settle below the 100 mA maximum continuous switching current after its initial transient.
400 kHz Isolated Pulse Generation
The isolated outputs can generate pulses at frequencies up to 400 kHz with a minimum pulse width of 1 µs. This allows the PCI-6624 to provide industrial-voltage pulse outputs without a separate TTL-to-industrial-voltage conversion stage in many applications.
Typical uses include sensor simulation, external equipment triggering, pulse-train generation and controlled test stimulus. The output load and external power supply must support the requested switching frequency.
32-Bit Counting Resolution
Each counter can count from zero through 4,294,967,295 before rolling over. This wide count range is useful for long-duration event counting and position tracking.
Software should account for rollover when a measurement can exceed the 32-bit range. Continuous applications can calculate count differences between successive readings to maintain an extended software count.
20 MHz and 100 kHz Timebases
The PCI-6624 provides 20 MHz and 100 kHz internal timebases. The 20 MHz timebase offers 50 ns nominal timing increments, while the 100 kHz timebase offers a longer interval before a 32-bit count rolls over.
| Timebase | Nominal Period | Approximate 32-Bit Rollover Time |
|---|---|---|
| 100 kHz | 10 µs | 11.93 hours |
| 20 MHz | 50 ns | 214.74 seconds |
The appropriate timebase depends on the required resolution and measurement duration. A faster timebase provides finer timing resolution but reaches the maximum 32-bit count sooner.
Frequency and Period Measurement
The PCI-6624 can determine signal frequency by counting edges or measuring the interval between successive transitions. It can also perform continuous buffered measurements when the application requires a sequence of frequency or period values.
Period measurement is useful for low-frequency signals, while buffered edge counting can support higher-frequency event streams. Measurement settings should be selected according to frequency range, required resolution and update rate.
Pulse-Width Measurement
The counter/timers can measure the high or low duration of a pulse. This capability is useful for checking duty cycle, monitoring control pulses and validating the timing response of industrial equipment.
Input propagation delay and the 1 µs minimum isolated pulse width should be included when evaluating measurement accuracy at the maximum field-interface frequency.
Quadrature Encoder Measurement
The PCI-6624 supports quadrature encoder position measurement using phase A and phase B signals. An additional input can be used for an encoder index or related control signal.
Channel-to-channel isolation is valuable when multiple encoders are installed on separate motors or mechanical assemblies with different electrical reference potentials.
Encoder output voltage, frequency, polarity and signal type must remain compatible with the isolated input specifications. External termination may be required for certain encoder interfaces.
Two-Signal Edge-Separation Measurement
The device can measure the time between an edge on one signal and an edge on another signal. This feature is useful for propagation-delay testing, mechanical timing measurements and comparing related control events.
The start and stop edges, signal polarity and expected timing range can be configured through NI-DAQmx according to the application.
Retriggerable Pulse Generation
The PCI-6624 can generate a new output pulse each time it receives a valid trigger. Retriggerable operation is useful when an external event must produce a consistent, hardware-timed response.
Applications include pulse stretching, delayed actuation, equipment triggering and converting irregular external events into standardized output pulses.
Channel-to-Channel Isolation
The PCI-6624 provides 60 VDC channel-to-channel isolation and 60 VDC channel-to-ground isolation for Measurement Category I circuits. Individual counters can therefore interface with signals using different field references.
Isolation helps reduce ground loops and limits the transfer of common-mode disturbances between field channels and the computer. It does not eliminate the need for appropriate wiring, grounding, shielding and circuit protection.
Input Overvoltage Protection
The isolated inputs include current limiting and reverse-voltage protection. They tolerate continuous reverse or overvoltage conditions up to ±60 VDC within the official protection specifications.
The protection circuitry improves industrial reliability but should not be treated as permission for continuous operation outside the normal 48 V input range. External surge suppression may be required in installations exposed to high-energy transients.
Output Short-Circuit Protection
If an output short circuit is detected, the PCI-6624 switches the affected output off. It retries approximately every 250 ms and automatically resumes operation after the short circuit is removed.
This self-recovery function reduces the likelihood that a temporary wiring fault will permanently interrupt the test. Appropriate external fusing should still be used when the field supply can deliver hazardous energy.
Three DMA Transfer Channels
The PCI-6624 supports DMA transfers for as many as three counter channels at the same time. DMA moves buffered data between the device and computer memory with reduced processor involvement.
Additional buffered operations can use interrupt-based transfers, depending on task configuration and available system resources. The complete application should be tested at its intended event rate and buffer size.
RTSI Trigger and Clock Routing
The PCI version provides seven RTSI trigger lines and one RTSI clock connection. An RTSI cable can route timing and trigger signals between compatible PCI data acquisition devices installed in the same computer.
This allows the PCI-6624 to coordinate measurements with another counter/timer, multifunction data acquisition device or compatible digital I/O board.
Typical PCI-6624 Applications
- Industrial event counting
- 48 V sensor monitoring
- Quadrature encoder position measurement
- Motor and shaft-speed measurement
- Измерение частоты и периода
- Pulse-width and duty-cycle measurement
- Pulse and pulse-train generation
- Retriggerable pulse generation
- Two-signal edge-separation measurement
- Automotive controller testing
- Aerospace equipment validation
- Industrial motion monitoring
- Manufacturing test systems
- Machine-cycle counting
- Sensor and actuator simulation
Automotive and Aerospace Testing
The PCI-6624 can monitor and generate isolated pulse signals used by automotive and aerospace controllers. Channel isolation helps when individual signals originate from separate electrical domains.
Test applications can measure sensor frequency, pulse width and encoder position or generate industrial-voltage pulses that simulate supported field devices. The complete test fixture must include suitable protection for the connected controller and power supply.
Industrial Motion Monitoring
The device can monitor multiple encoders, speed sensors and machine-cycle signals in one computer. Hardware counters capture pulses independently of normal software execution timing.
The PCI-6624 provides measurement and pulse-generation functions but is not a complete safety-rated motion controller. Machine stopping, personnel protection and emergency functions require appropriate external safety equipment.
Manufacturing Test Systems
In production equipment, the PCI-6624 can count parts, measure rotational speed, monitor fixture motion and generate synchronized test pulses. Its isolated industrial interface reduces the need for separate signal-conditioning components.
Buffered counter measurements and DMA transfers help maintain throughput when a test must collect a sequence of timing values rather than only a single counter reading.
NI-DAQmx Software Support
The PCI-6624 is controlled through NI-DAQmx. The driver provides functions for event counting, frequency measurement, period measurement, pulse-width measurement, encoder position measurement and counter output generation.
NI-DAQmx supports LabVIEW, LabWindows/CVI, C, C++ and compatible .NET programming environments. NI Measurement & Automation Explorer can be used to confirm device recognition and inspect available terminals and routes.
PCI System Integration
The PCI-6624 requires a conventional PCI expansion slot. It cannot be installed directly in a PCI Express slot.
Before ordering, verify the computer’s slot type, operating system and compatible NI-DAQmx version. Also confirm that sufficient space is available for the 100-pin cable and that the field wiring remains accessible after installation.
PCI-6624 Wiring Considerations
The PCI-6624 uses a 100-pin female SCSI-II connector. Because each isolated input uses two terminals and each counter includes multiple signals, careful pinout verification is required before applying field power.
Use shielded cabling for electromagnetic compatibility and route signal wiring away from motors, contactors and high-current cables. Do not exceed 60 VDC between any two I/O channels or between a channel and earth ground.
PCI-6624 Troubleshooting
The PCI-6624 is not detected in NI MAX
Confirm that the board is fully installed in a compatible conventional PCI slot. Check computer firmware settings, install a supported NI-DAQmx version and restart the computer before rescanning for hardware.
An input does not detect the field signal
Measure the voltage across the positive and negative terminals of the selected isolated input. Confirm that the signal reaches the guaranteed 4.1 V ON threshold and that the correct counter source, gate or auxiliary terminal is configured.
The counter records extra pulses
Inspect the signal for noise, contact bounce, ringing or an unstable field reference. Improve cable shielding, grounding and sensor wiring, and apply supported filtering when appropriate.
The counter misses valid pulses
Confirm that the field signal remains below 400 kHz and provides at least the required 1 µs pulse width. Check signal amplitude, edge quality, software configuration and external wiring capacitance.
An output does not switch the load
Verify that an external supply between 5 VDC and 48 VDC is connected correctly. Confirm that the load is wired for a sinking low-side output and that its continuous current does not exceed 100 mA.
An output repeatedly turns off and on
This behavior can indicate that the short-circuit protection is retrying the output. Disconnect the load and check for a short circuit, excessive inrush current, reversed wiring or an unsuitable field supply.
An encoder counts in the wrong direction
Reverse the phase A and phase B connections or change the counting-direction configuration. Confirm the selected quadrature decoding mode and mechanical scaling.
A buffered task reports transfer problems
The device supports up to three simultaneous DMA transfers. Review the number of buffered tasks, input frequency, buffer size and system workload. Additional tasks may need interrupt-based transfers.
Channels interfere with one another
Check that each isolated channel uses the correct positive and negative field terminals. Do not unintentionally join channel references in the terminal block or external fixture.
PCI-6624 Comparison with Similar Counter/Timer Devices
| Модель | Primary Configuration | Interface | Best Suited For |
|---|---|---|---|
| PCI-6624 | 8 counters, 48 V isolated I/O, 400 kHz field interface | PCI | Industrial counter/timer applications using conventional PCI |
| PXI-6624 | 8 counters, 48 V isolated I/O, 400 kHz field interface | PXI | Industrial counter/timer measurements in modular PXI systems |
| PCI-6602 | 8 counters, 5 V TTL I/O, 80 MHz timebase | PCI | Higher-speed TTL counter and encoder measurements |
| PCI-6601 | 4 counters, 5 V TTL I/O, 20 MHz timebase | PCI | Lower-channel-count TTL timing applications |
| PCIe-6612 | 8 counters with TTL/CMOS-compatible I/O | PCI Express | Modern PCI Express counter/timer systems |
PCI-6624 vs PCI-6602
The PCI-6624 and PCI-6602 both provide eight 32-bit counters, but they are optimized for different signal environments. The PCI-6624 provides channel-isolated field I/O up to 48 VDC, while the PCI-6602 is designed primarily for faster 5 V TTL/CMOS signals.
Choose the PCI-6624 when isolation and industrial voltage compatibility are more important than maximum speed. Choose the PCI-6602 when the application requires an 80 MHz timebase and direct TTL-level connectivity.
PCI-6624 vs PXI-6624
The PCI-6624 and PXI-6624 provide substantially similar isolated counter/timer functionality. The principal difference is the platform: the PCI model installs in a conventional desktop or industrial computer, while the PXI model installs in a PXI chassis.
Select the PCI-6624 for an existing computer-based system with a PCI slot. Choose the PXI-6624 when modular PXI integration, chassis triggering and coordinated operation with other PXI instruments are required.
Recommended Related Products
- PXI-6624 8-Channel Isolated 48 V Counter/Timer Module
- PCI-6602 8-Channel 32-Bit Counter/Timer Device
- PCI-6601 4-Channel Counter/Timer Device
- PCIe-6612 8-Channel PCI Express Counter/Timer Device
- PXI-6602 8-Channel PXI Counter/Timer Module
- View More NI PCI and USB Data Acquisition Products
- View More NI PXI and PXI Express Modules
Selecting the Right Counter/Timer Device
Choose the PCI-6624 when the application requires eight 32-bit counters, channel-to-channel isolation and direct compatibility with field signals up to 48 VDC. It is particularly suitable for industrial encoders, automotive signals and isolated manufacturing-test fixtures.
Select the PCI-6602 when higher-speed TTL timing is required. Choose the PXI-6624 for modular PXI installations or the PCIe-6612 when developing a new computer-based system around PCI Express.
Why Choose the PCI-6624?
- Interfaces directly with industrial signals up to 48 VDC
- Provides eight independent 32-bit counters
- Includes 26 isolated inputs and eight isolated outputs
- Supports 400 kHz field input and output signals
- Provides channel-to-channel isolation
- Measures encoders, frequency, period and pulse width
- Generates single, continuous and retriggerable pulses
- Includes reverse-voltage and overvoltage protection
- Protects outputs against short circuits
- Supports buffered DMA measurements
- Integrates with NI-DAQmx and LabVIEW
Frequently Asked Questions
What is the PCI-6624?
The PCI-6624 is an eight-channel industrial counter/timer device with channel-to-channel isolated inputs and outputs supporting field voltages up to 48 VDC.
What is the PCI-6624 part number?
The standard NI part number for the PCI-6624 is 778834-01.
How many counters does the PCI-6624 provide?
It provides eight independent 32-bit up/down counter/timers.
How many isolated inputs are available?
The device has 26 isolated inputs: three for each of the eight counters plus two additional programmable function inputs.
How many outputs are available?
The PCI-6624 provides eight isolated counter outputs.
Are the outputs sourcing or sinking?
The outputs are sinking, low-side switches. The connected load requires an external field supply between 5 VDC and 48 VDC.
What is the maximum output current?
Each output can switch up to 100 mA continuously and supports inrush current up to 600 mA.
What is the maximum isolated input frequency?
The maximum frequency through the isolated field input interface is 400 kHz, with a minimum input pulse width of 1 µs.
Can the PCI-6624 measure quadrature encoders?
Yes. It supports quadrature encoder position measurement using phase A, phase B and an optional index or auxiliary signal.
Can it generate pulse trains?
Yes. The PCI-6624 supports pulse generation, continuous pulse trains, buffered pulse measurements and retriggerable pulse applications.
What isolation rating does it provide?
It provides 60 VDC channel-to-channel and channel-to-ground isolation for Measurement Category I circuits.
Does the PCI-6624 accept TTL signals?
Yes. Its guaranteed ON threshold is 4.1 V, allowing supported 5 V signals to be detected. It also accepts higher-voltage industrial signals up to 48 VDC.
Which cable is compatible with the PCI-6624?
The recommended cable is the SH100M-100M Flex. Part number 185095-01 is the 1 m version, and 185095-02 is the 2 m version.
Which terminal block is recommended?
The SCB-100A shielded screw-terminal connector block, part number 785024-01, is the recommended direct 100-pin connectivity option.
Does the PCI-6624 fit a PCI Express slot?
No. It requires a conventional PCI slot and cannot be installed directly in a PCI Express slot.
Request a Quote for the PCI-6624
Contact us for current availability, condition, lead time and project pricing for the PCI-6624 8-Channel Isolated 48 V Counter/Timer Device. We can also help identify compatible SH100M-100M Flex cables, SCB-100A terminal blocks and related PCI, PCI Express or PXI counter/timer hardware.
