Digital Input Modules for Compact FieldPoint

Overview

National Instruments cFP-DI-3xx devices are versatile digital input

modules available for Compact FieldPoint systems. You can use these

modules to monitor digital signals ranging from low-voltage levels up to

250 V. They are commonly used to monitor proximity and limit switches,

pushbutton switches, thermostat outputs, relay closures, power circuits,

and TTL devices. All the modules include onboard diagnostics to ensure

trouble-free installation and maintenance.

Digital Input Modules

The cFP-DI-3xx modules provide built-in module-to-module isolation to

protect your Compact FieldPoint system and controller or communication

interface from high voltage levels. The cFP-DI-300, cFP-DI-301, and

cFP-DI-304 modules use a common ground plane for all the input

channels. Each channel on the cFP-DI-300, cFP-DI-301, and cFP-DI-304

modules includes current-limiting circuitry to prevent module damage

when connected directly to a 24 VDC source. The cFP-DI-330 uses eight

optically isolated input channels so that each digital input has a separate

ground plane, and you can use each channel with a different voltage

potential. Thus, you can connect one channel to a 5 VDC TTL signal and

another signal on the same cFP-DI-330 module to a 250 VAC line voltage.

Each channel on the cFP-DI-330 includes circuitry that limits the total

current to 1.5 mA to prevent damaging the module. All channels on the

cFP-DI-3xx modules feature LEDs that indicate the input state of each

channel. The modules include an all-channel update rate of 1 kHz. Overall

data throughput depends on software loop speeds and network speeds.

Isolation

breakdown isolation. In addition, the cFP-DI-330 provides double insulation

FieldPoint with the cFP-CB-1 connector block in applications where

hazardous voltages are present. These Compact FieldPoint modules do

not have channel-to-channel isolation.

Field I/O Connections

Compact FieldPoint modules include a built-in power distribution bus

that provides multiple power connections on the module. A field-wired

power supply connected to the voltage (V) and common (C) terminals is

internally connected to a power distribution bus that delivers additional

terminals offer a convenient way to distribute power to field devices

that require external power.

• 8-,16-, or 32-channel inputs

• 24 VDC inputs

• 4 to 250 VDC inputs

• 15 to 250 VAC inputs (50/60 Hz AC)

• 3 to 250 VAC inputs (1 kHz AC)

overvoltage protection

• Hot-swappable with autoconfiguration

• -40 to 70 °C operating range

NI cFP-DI-300, NI cFP-DI-301,

NI cFP-DI-304, NI cFP-DI-330

Module

Input Channels

Input Ranges

Input Type

Compatibility Examples

Separate Ground

Plane per Channel

All Channel

Update Rate1

Additional

Features

cFP-DI-300

8

18 to 30 VDC

Sinking

24 VDC sourcing devices

–

1 kHz

–

cFP-DI-301

16

18 to 30 VDC

Sinking

24 VDC sourcing devices

–

1 kHz

–

cFP-DI-304

32

10 to 30 VDC

Sinking

24 VDC sourcing devices

–

1 kHz

Hysteresis

cFP-DI-330

8

5 to 48 VDC

5 to 250 VAC

Sinking or sourcing

TTL, CMOS, 12 VDC, 24 VDC,

48 VDC, 120/240 VAC/VDC



1 kHz

Input current limiting

(1.5 mA)

1

The all-channel update rate refers to the time the module takes to sample all channels. The overall system update rate is affected by other factors, such as the aggregate module update rate and