RAD128 Remote Analog Input and Digital I/O Pod Family
8-channel, 12-bit analog input pod with isolated RS-485, digital I/O, and counter/timers
Features
- Eight single-ended analog inputs with software-selectable ±10 V, ±5 V, 0-10 V, and 0-5 V ranges
- 12-bit A/D conversion at up to 10,000 conversions per second in foreground mode
- AIM-16 multiplexer and signal-conditioning expansion support
- Seven programmable digital I/O lines plus one dedicated input
- Eight additional TTL outputs for multiplexer control or general use
- Three 16-bit counter/timers with a 10 MHz clock
- Optically isolated RS-485 and ASCII command/response protocol
- On-board microcontroller, memory, and watchdog timer
- Compact NEMA 4 enclosure
- USB, wireless, Ethernet, and RS-232 connectivity packages available
- Designed and manufactured in the USA
$385.00
In StockDescription
The RAD128 is an intelligent remote analog-input and digital-I/O pod with an optically isolated RS-485 interface. Eight single-ended analog inputs provide 12-bit resolution, and each channel can be programmed for ±10 V, ±5 V, 0-10 V, or 0-5 V. The on-board microcontroller supports acquisition and local buffering independently of immediate host polling.
Serial Communications and Acquisition
An ASCII command/response protocol supports applications written in languages with serial and string functions. Up to 31 pods can share a two- or four-wire multidrop network, with each unit responding only when addressed by the host. Module addresses and baud rates are software programmable and retained in EEPROM. Low-attenuation twisted-pair wiring supports RS-485 runs up to 4,000 feet.
The converter supports 10,000 conversions per second in foreground mode and 6,670 conversions per second in background mode. Software commands or an on-board programmable timer initiate acquisition. Input data can be buffered locally for later retrieval.
Analog Expansion
AIM-16 multiplexers and signal conditioners extend the input system for additional channels, differential measurements, alternate voltage ranges, and low-level sensor signals. Each AIM-16 provides sixteen single-ended or differential channels with programmable gain. The pod provides the gain and channel-selection outputs used to control these expansion boards.
Digital I/O and Counter/Timers
The general-purpose digital interface has seven individually programmable input/output bits and one dedicated input. Open-collector outputs support application voltages up to 50 VDC and a maximum sink current of 350 mA per line, with a combined 650 mA limit. Eight additional TTL outputs provide multiplexer gain and channel control or general-purpose outputs when those functions are unused.
Three 16-bit counter/timers include one uncommitted counter and two cascaded counters used for timed A/D acquisition. The uncommitted counter exposes clock, gate, and output signals for application use and accepts clock inputs up to 10 MHz. A watchdog timer helps recover from processor and supply faults.
Installation and Power
The compact NEMA 4 enclosure provides internal screw terminals and sealed cable entry for remote field installation. Separate local and isolated-interface supplies maintain serial isolation. The U-, WM-, E-, and S-prefix packages provide USB, wireless, Ethernet, and RS-232 host connectivity respectively.
Customized Analog I/O (MCOTS Options)
ACCES specializes in modified-COTS analog I/O. We can customize voltage ranges, sampling rates, filtering, isolation, gain stages, calibration profiles, firmware behavior, connector styles, and environmental ruggedness. If your analog requirements are unique, we excel at delivering tailored MCOTS analog hardware quickly and cost-effectively.
Analog Inputs
| Input channels | Eight single-ended inputs with common ground |
|---|---|
| Resolution | 12 bits |
| Input ranges | Software selectable on each channel: ±5 V, ±10 V, 0-5 V, and 0-10 V |
| Throughput | 10,000 conversions/s in foreground mode; 6,670 conversions/s in background mode |
| Converter | Successive approximation |
| Trigger source | Software command or on-board programmable timer |
| Gain drift | ±5 ppm/°C |
| Input impedance | 21 kΩ unipolar; 16 kΩ bipolar; 10 MΩ with AIM-16 |
| Coding | True binary for unipolar inputs; offset binary for bipolar inputs |
| Accuracy | 0.025% ±1 LSB (estimated) |
Digital I/O
| General-purpose lines | Seven programmable input/output bits plus one dedicated input |
|---|---|
| Input logic high | 2-50 V; 5 mA maximum at 50 V |
| Input logic low | -0.5 to +0.8 V at 0.4 mA maximum |
| Output type | Open collector with inductive-suppression diodes |
| Output compliance | Up to 50 VDC user-supplied application voltage |
| Output-current limits | 350 mA maximum per line; 650 mA maximum combined |
| Pull-ups | 10 kΩ to +5 V when no application voltage is supplied |
| Additional digital outputs | Eight TTL outputs, each capable of driving 10 LSTTL loads; GN0-GN2 and SEL0-SEL3 control an optional multiplexer, OP4 is general purpose |
Counter/Timers
| Timer type | 82C54-2 programmable interval timer |
|---|---|
| Counters | Three 16-bit down counters; two cascaded for timed A/D conversions and one uncommitted counter |
| Clock frequency | DC to 10 MHz; on-board 10 MHz crystal clock |
| Timer output drive | 4 mA at 0.4 V (10 LSTTL loads) |
| Active edge | Negative |
| Minimum clock pulse width | 30 ns high; 50 ns low |
| Timer range | 2.5 MHz to less than one pulse per hour |
Serial Interface
| Interface | Optically isolated RS-485; ASCII command/response protocol |
|---|---|
| Baud rates | 1200, 2400, 4800, 9600, 14400, 19200, 28800, and 57600 |
| Data format | 7 data bits, even parity, one stop bit |
| Module address | 00-FF hexadecimal, software programmable and retained in EEPROM |
Power
| Local supply | 7.5-16 VDC at 150 mA |
|---|---|
| Isolated serial-interface supply | 7.5-25 VDC at 40 mA |
| Isolation power arrangement | Separate local and isolated supplies maintain the serial-interface isolation; isolated power may be carried over a four-wire communications cable |
Environmental and Mechanical
| Operating temperature | 0 to +65 °C; optional extended range -40 to +80 °C |
|---|---|
| Temperature derating | Maximum ambient temperature depends on applied supply voltage; see the hardware manual |
| Storage temperature | -20 to +70 °C |
| Relative humidity | 5-95%, non-condensing |
| Enclosure | NEMA 4, 4.53 × 3.54 × 2.17 inches |
Select the model for the required input configuration and host connection. The base model uses isolated RS-485. U-, WM-, E-, and S-prefix versions provide USB, wireless, Ethernet, and RS-232 connectivity packages. Contact ACCES for pricing and availability of these connectivity packages.
Call for Pricing
- U-RAD128 — RAD128 USB connectivity package
- WM-RAD128 — RAD128 wireless connectivity package
- E-RAD128 — RAD128 Ethernet connectivity package
- S-RAD128 — RAD128 RS-232 connectivity package
| Model | Description | Price (USD) | |
|---|---|---|---|
| RAD128 | RAD128 remote 8-channel 12-bit analog-input and digital-I/O pod with isolated RS-485 | $385.00 | |
| U-RAD128 | RAD128 USB connectivity package | Call for price | |
| WM-RAD128 | RAD128 wireless connectivity package | Call for price | |
| E-RAD128 | RAD128 Ethernet connectivity package | Call for price | |
| S-RAD128 | RAD128 RS-232 connectivity package | Call for price |