PCI-6514 | Product Overview

The NI PCI-6514 is a National Instruments (NI) industrial-grade 64-channel isolated DIO (32 isolated input + 32 isolated source output, ±30 V, 8 groups of isolation, high current), PCI bus, half-length card, featuring:

32 isolated DI (Sink/Source compatible, ±30 V, 12.5 mA) + 32 isolated DO (Source, 75 mA per channel, peak 350 mA, 8 groups of independent optocouplers, watchdog, programmable power-on state)

Suitable for 24 V sensors / proximity switches / button inputs + relays / solenoids / LED outputs, factory automation, mixed switch quantity control in strong interference environments.

Part number: 778836-01; discontinued (EOL), replacement model: PCIe-6514.

I. Basic Information

Model: PCI‑6514

Brand: National Instruments (NI)

Series: 651x Industrial Isolated DIO Series

Bus: PCI (5 V compatible, half-length card)

Connector: 1 × 100-pin SCSI (high density)

Isolation: 64 channels divided into 8 groups (Bank 0–7, 8 channels per group: 4 DI + 4 DO), optical isolation between groups

Driver: NI-DAQmx

Operating Temperature: 0 ~ 55 °C

Features: ±30 V withstand voltage, 8 groups of isolation, 32 DI + 32 DO, Source output 75 mA, programmable input filtering, watchdog, programmable power-on state, high immunity to interference

II. Digital Input DI (32 channels, isolated type, Sink/Source compatible)

Channels: 32 isolated digital inputs, 8 groups × 4 channels/group

Input Voltage Range: ±30 VDC (compatible with 5/12/24 V industrial logic)

Input Current: 12.5 mA/channel (maximum, 30 V input)

Input Type: Sink/Source compatible (NPN/PNP sensors can be connected)

Logic Levels:

High Level: ≥ +2 V (typical +5 ~ +30 V)

Low Level: ≤ +0.8 V (typical 0 ~ ‑30 V)

Input Filtering: Programmable (software debounce, eliminates spikes / contact jitter)

Maximum Input Rate: Approximately 1 MHz (software dependent)

Functions: Single-point reading, group reading, rising/falling edge detection, counter triggering

III. Digital Output DO (32 channels, isolated type, Source output)

Channels: 32 isolated digital outputs, 8 groups × 4 channels/group

Output Voltage Range: 0 ~ +30 VDC (Source output, high active)

Load Current:

Continuous: 75 mA/channel

Peak (pulse): 350 mA/channel

Output Type: Source (source type), outputs high voltage to drive loads

On-Resistance: Low resistance, typical < 1 Ω

Power-On State: Programmable (high/low/hold)

Maximum Switching Rate: Approximately 100 kHz (software dependent)

Functions: Single-point control, group control, pulse output, PWM (software), fail-safe shutdown

IV. Industrial Characteristics

Watchdog Timer: Programmable timeout (1–65535 ms), automatically cuts safe output (high/low) when fault occurs

Programmable Power-On State: Prevents accidental actions during power-on

Programmable Input Filtering: Software debounce, suitable for mechanical switches / relays

Group Independent Isolation: 8 groups completely independent, can be connected to different voltage domains, suppresses ground loop interference

High Common-Mode Suppression: Suitable for motors, frequency converters, relays, etc. with strong interference

Overcurrent / Overvoltage Protection: Single-channel current limiting, prevents short circuit damage

V. Physical and Environmental

Size: Half-length PCI, approximately 12.4 cm × 12.6 cm × 2.2 cm

Weight: Approximately 0.15 kg

Temperature: 0 ~ 55 °C (operating), -20 ~ 70 °C (storage)

Humidity: 10% ~ 90%, no condensation

Isolation Voltage: ≥ 500 Vrms (between groups / to ground)

Power Consumption: +5 V @ 150 mA; +3.3 V @ 300 mA (typical)

VI. Installation and Usage Tips

Installation

Turn off and disconnect power, insert into a standard PCI half-length slot; After startup, it is identified as MAX and NI-DAQmx is installed.

Wiring (100-pin SCSI)

8 independent isolated grounds: Each group's ground is isolated from the system ground to avoid ground loops.

DI wiring: NPN sensors (Sink) → Connect the signal to DI, and the sensor ground is connected to the ground of this group; PNP sensors (Source) → Connect the signal to DI, and the positive pole of the sensor is connected to +24 V.

DO wiring (Source): Connect the DO to the positive pole of the load, and the negative pole of the load is connected to the ground of this group (24 V load).

Load voltage: 0 - 30 VDC, recommended 24 V industrial standard.

Do not short circuit: Single channel current limiting, long-term short circuit will trigger protection.

Capacitive loads (relays / solenoids): It is necessary to parallel a shunt diode (1N4007) to prevent reverse high voltage from breaking the board.

Software configuration (NI-DAQmx)

DI: Enable input filtering (debouncing 5–20 ms), suitable for mechanical switches.

DO: Source type output, power-on low level, watchdog 100–500 ms safe low level.

Output rate: Relay control is recommended ≤ 10 Hz to avoid contact burnout.

Notes

8 independent isolated groups, group-to-group withstand voltage ≥ 500 Vrms, can be mixed with different voltage DI/DO.

Long lines use shielded cables, the shield is connected to the ground of this group, and not connected to the system ground.

Not suitable for directly connecting >30 V loads, need to add an intermediate relay for conversion.

Capacitive loads must be connected with a shunt diode, otherwise they are prone to damage the output channel.

Seven, Core Features

32 isolated DI (±30 V, Sink/Source compatible, 12.5 mA, programmable filtering) + 32 isolated DO (Source, 75 mA / channel, peak 350 mA)

PCI half-length card, 100-pin SCSI, NI-DAQmx, 8 independent optocouplers, watchdog, programmable power-on / filtering, high anti-interference

Directly connect 24 V sensors / switches + relays / solenoids / LEDs, mixed DIO for strong interference sites, factory automation I/O station

Applicable: 32 input 32 output isolated control, sensor acquisition + actuator drive, production line I/O, relay control cabinet, DIO in strong interference environment