4. A Tour of RAD-IO2 Hardware

4.1. RAD-IO2-TC Thermocouple Module

8 Banks; ONE channel per bank
Each Bank has it’s on CJC and A/D chip 16 BIT Delta Sigma Converter
“K” Type only
K-Type range -270C to 1260C; +/- 2C accuracy
60Hz and 50Hz common mode rejection > 105dB
ISOLATED- Since each bank is isolated from another, and there is one thermal couple channel per bank, the effect is that the system has channel to channel isolation- this is without using miniature relays as a multiplexer, which cause a lot of settling time and error.
Although thermocouples are not as accurate as RTD’s, with the high quality of the RAD-IO2-TC, (especially Intrepid calibrates each channel), The RAD-IO2-TC unit is 0.2°C resolution; accuracy better than +/- 1° C is typical.
Thermocouples are NOT included in production shipments. Go to Omega.com or similar supplier to purchase thermocouples.

4.2. RAD-IO2-AIN Analog Input Module

There are 8 “Banks”, each bank has an one A/D chip 16 BIT Delta Sigma Converter with a Low range and a high range input, you can connect only to the Low or the High not both at the same time.
- Low range ± 250 mV, ± 1000 mV, ± 5000 mV
- High range ± 10V, ± 20V, ± 45V
- DO NOT exceed the maximum voltage for each range or damage will occur to the unit!
You can use the AIN module like 8 totally independent “floating” voltmeters without fear of one channel influencing the other.
Sampling rate: Max 1000 sps (samples per second) aggregate across all daisy chained modules OR max 100 samples per sec channel. For example, 24 channels would yield 1000 / 24 = ~41 samples per second. One channel would yield 100 samples per second.
RAD-IO2-AIN is great for most static or semi-static measurements but to slow for Electrical
Transients, Microphones, Accelerometers.
The RAD-IO2-AIN is 16 Bit resolution, however it is a Delta-sigma (ΔΣ) analog-to-digital converters (ADCs) so less “jitter” is obtained when slower conversion speeds are used as samples are averaged by the A/D chip internally.
“Delta-sigma (ΔΣ) analog-to-digital converters (ADCs) are based on the principle of oversampling. The input signal filtered and decimated in the digital domain to yield a conversion result at the respective output data rate.

4.3. RAD-IO2-AOUT- Analog Output Module

8 banks of isolated output, each DAC (Bank) has three 0-5V analog outputs and one common ground line per bank, for a total of 24 Analog Outputs
16bit DAC (76.3uV per bit)
5mA output current per channel, this is limited by the drive chip.
If all channels were outputting the maximum current, the approximate current draw would be 370mA.
Please note, the same 100 samples per second limitation applies when you try to update the analog signal output.

4.4. RAD-IO2-PWRRLY Power Relay module

8 isolated Form C relays. Each relay has a normally open and normally closed connection. The two common connections (pin 2 and pin 3) are tied together internally.
Switching current is 5A for DC voltages up to 220VDC, and 5A for 250VAC, switching power is 60W/62.5VA
Switching material is AgNi (Silver and Nickel) and gold plated; Initial contact resistance is <50mΩ at 10mA/30mV
High mechanical shock resistance up to 50g functional
Electrical endurance
- (≤30mV/≤10mA) min. 2.5M operations
- cable load open end min. 2M operations
- resistive, 220 VDC / 0.27A - 60W min. 500k operations
Max DC load Breaking capacity

4.5. RAD-IO2-DIO Digital In/Out module

Includes 8 isolated banks with one common ground per bank for a total of 12 inputs and 8 outputs. The first 4 banks are inputs and the second 4 banks are outputs, all banks are isolated from each other.

Digital Inputs:

The four isolated input banks inputs have three 0-40V 12bit ADC inputs per bank (12 total), which can be reconfigured during operation in 5 different modes:

0-40 VDC analog input, the value reported back will be an analog value

Digital input with a programmable threshold (in 160mV steps), the value reported back will be an digital (0 or 1) value

PWM input with programmable voltage threshold (in 160mV steps), the value reported back will be an digital (0 or 1) value

Period measurement

Frequency measurement

Digital Outputs:

The 4 isolated output banks each have two digital outputs that can be configured as separate digital channels (half bridge) or can be joined as a full H-Bridge output. There are four pairs of outputs for 8 total. Each output can pass 5.5V to 40V at 6A (user supplied).

The RAD-IO2-DIO Digital Output uses one BTN8962TA chip for each output.

They can be configured as:

A simple Digital output,
A One Shot output
PWM and frequency programmable output

As Half Bridge

When in FULL BRIDGE MODE