Multifunction analog/digital I/O w/serial COM | Model 2426

Description

Model 2426 is a versatile open-frame module that interfaces a variety of real world signals to a 10/100 Mbps Ethernet. It has eight optically isolated digital inputs, 16 digital outputs, six 12-bit analog inputs, one 12-bit analog output, an asynchronous serial port with RS-422/RS-485 phy, and a high speed incremental encoder interface, all powered by an external 24 VDC supply (not included). The module's compact footprint allows it to fit into tight spaces, and the built-in DIN rail mounting hardware makes installation quick and easy.

2426 Block Diagram

Network servers

Remote network clients communicate with the module via its built-in servers (telnet for manual and automated control; HTTP for configuration, manual control, and diagnostics), which allows any web browser or telnet client to remotely monitor and control I/O without any special device drivers or proprietary software. In the case of telnet, commands and replies are conveyed in plaintext, which can dramatically reduce development time and simplify maintenance.

2426 Control page screenshot

Control page viewed on an HTC Hero (Google Android) browser

Software development kit

A free software development kit is available for model 2426 which includes documentation, sample applications and a comprehensive application program interface (API). Pre-built API libraries are included for Linux and Windows, along with API source code (C language) and instructions for OEM customization and porting.

The API transparently handles all of the underlying telnet and module command protocols so that programmers can focus on application development. For example, application software can simply call the s2426_WriteDout() function to program the general purpose digital outputs.

Concurrent access

The module supports simultaneous communication with multiple clients. For example, maintenance personnel can plug into the network and monitor the module while, at the same time, the module is controlled by an automation process running on another computer.

Furthermore, the API allows any process to utilize multiple concurrent sessions. A typical application of this is to have one thread handle RS-422/RS-485 serial communication while another thread interacts with I/O interfaces on a separate session, resulting in straightforward application code that tends to be robust and easily maintained.

Watchdog timers

A hardware watchdog timer will reset the module in the event of an internal module malfunction. In addition, a communication watchdog will trigger a module reset if a client fails to communicate with the module in a timely manner. In both cases, the reset will automatically force all outputs to "safe" states.

Support for safety interlocks

Each digital output can be configured to unconditionally deactivate its output driver when an associated contact (e.g., safety interlock, emergency stop switch) is open. Implementing this commonly required feature in the module allows external termination boards to be eliminated and wiring to be simplified, with a commensurate reduction in system complexity and cost.

Digital output block diagram

Typical interlock application

Accessories

2426TA termination board

An optional breakout termination board, model 2426TA, is available for model 2426. It plugs directly onto the 2426 module with board-to-board interconnects — minimal overhead space is used and no cables are needed. Field wiring can then be quickly and easily inserted into the 2426TA's spring terminal blocks.

2426TA breakout termination board

Specifications

Communication Interfaces
Network	Physical layer	10BaseT, 100BaseTx Ethernet
	Bit rate	10/100 Mbps, auto-detecting
	Isolation	1500Vrms
	Protocols	ARP, ICMP, IPv4, TCP, TELNET, HTTP
	Configuration	Programmable via HTTP (static ARP): IP address, netmask, gateway
HTTP Server	Concurrent sessions	0 to 1
	Functions	Status, configuration, I/O monitor/control
TELNET Server	Concurrent sessions	0 to 3
	Time-out interval	5 minutes (default, reprogrammable via HTTP), programmable per session via shell
Async Serial COM	Physical layer	RS-422 or RS-485, shunt configurable
	Bit rate	300 bps to 115.2 Kbps, software selectable
	Termination (RS-422/485)	120 ohms ±5%, transmit and/or receive pair, enabled via shunts
	Receiver turnaround	250 µs maximum
	Telnet protocol options	Com Port Control (RFC 2217), Binary Transmission (RFC 856)
Timestamp Generator	Count rate	1.0 MHz
	Resolution	32 bits, 1.0 µs
Analog Interfaces
Analog Inputs	Channels	6 external, 2 internal reference
	Resolution	12 bits
	Input type	Differential
	Differential input range	-10V to +10V, minimum (at 0V CMV)
	CMV input range	-10V to +10V
	Input impedance	22M ohms minimum
	Conversion rate	1000 samples/s per channel
	Inter-channel acquisition skew	125 µs maximum
	Trigger	Internal hardware timer
	Data format	Signed 16-bit integer with timestamp
Analog Output	Resolution	12 bits
	Output range	-10V to +10V, minimum
	Settling time	500 µs maximum (20V step change)
	Data format	Signed 16-bit integer
Encoder Interface
Encoder Interface	Resolution	32 bits
	Count rate	0 to 30 MHz
	Clock rate	0 to 7.5 MHz
	Clock/Index input signals	RS-422 differential, TTL/5VCMOS compatible, ±7V CMV maximum
	Encoder power output	5VDC ±5%, 100mA maximum
	Data format	Signed 32-bit integer with timestamp
Digital Interfaces
Digital Inputs	Channels	8
	Input type	Differential pair, optically isolated with 4.7 Kohm series impedance
	Input range	+5V to +24V
Digital Outputs	Channels	16
	Output type	Active low, open collector drive with inductive load EMF suppression diode
	Output high-level voltage source	Internal, shunt selectable from continuous 24V or any interlock power source
	Output current	100 mA maximum per channel, 500 mA maximum total
Power and Environmental
Module Power	Input power	24VDC ±5% @120mA (digital outputs off, no external loads)
Interlock Power	Channels	5
	Voltage range	+5VDC to +24VDC, referenced to module input power
	Current	500mA maximum, per circuit
Temperature	Operating range	-25 to 85 °C
Mechanical
Module Dimensions	Outer dimensions	(W x H x D): 5.3 x 5.0 x 2.2 inches W = DIN rail length D = module height from DIN rail back panel; additional clearance required for field wiring.
Mating Connectors (*) = included with module	Ethernet	RJ-45 plug, AMP 554169 or equivalent
	Terminal block (*)	Pluggable TB, Phoenix Contact 17.92.83.8 or equivalent
	Serial COM	DB-9 male, Norcomp 171-009-102-001 or equivalent
	Encoder	DB-9 female, Norcomp 171-009-202-001 or equivalent
	Analog I/O	DB-25 female, Norcomp 171-025-202-001 or equivalent
	Digital inputs	DB-37 female, Norcomp 171-037-202-001 or equivalent
	Digital outputs	DB-37 male, Norcomp 171-037-102-001 or equivalent

Documentation

File	Version	Date M-D-Y	Type	Size
Model 2426 Technical Manual	1.0.1	10-17-24	PDF	357 KB
Model 2426 Mechanical Dimensions	1.0.0	10-17-24	PDF	188 KB
3D model	—	10-17-24	STEP	16.97 MB

Downloads

File	Version	Date M-D-Y	Type	Size
2426 Software Developer's Kit (SDK)	1.1.2	10-17-24	ZIP	1.78 MB
Other Operating Systems
Need a software development kit for another operating system? We can port our SDK to your OS for a NRE fee or, with a volume commitment, at no additional cost. Contact Sales for details.

Pricing & Ordering

Model	Description	Qty 1	Qty 2-9	Order Qty.
2426	Multifunction analog/digital I/O w/serial COM	$460	$417
Optional Accessories
2426TA	Termination board for Model 2426, top mounted	$167	$153