The unit's address is programmable from 00 to FF hex and whatever address is assigned is stored in EEPROM and used as the default address at the next power-on. Similarly, baud rate is programmable for 1200, 2400, 4800, 9600, 14400, 19200, and 28800. The programmed baud rate is stored in EEPROM and used as default at the next power-on. A type 8031 microcontroller (with 32K x 8 bits RAM and 32K x 8 bits EEPROM and a watchdog timer circuit) gives RAG128 the capability and versatility expected from a modern distributed control system. RAG128 contains lowpower CMOS circuitry, an opto-isolated receiver/transmitter, and power conditioners for local and external isolated power. It can communicate at baud rates up to 28.8K baud and distances up to 4000 feet with low-attenuation twisted pair cabling.
RAG128 accepts up to eight single-ended analog inputs. Input voltage ranges of ±10V, ±5V, 0-10V, and 0-5V are programmable on a channel-by-channel basis. All inputs are overvoltage protected up to 16.5V. The digitizer used is a 12-bit, successive approximation analog-to-digital converter capable of 10,000 conversions per second. Conversions may be initiated in one of three ways:
a. By software command.b. By an on-board programmable timer.c. By an external trigger.
The RAG128 can be used alone or it may be used with signal conditioners and analog sub-multiplexers AIM-16 and LVDT-8 or with simultaneous sample and hold amplifiers models SSH-04 and SSH-08.
• More than eight analog inputs.• Differential inputs rather than single- ended.• Different full-scale voltage ranges.• Inputs from thermocouples and other low-level voltage sources.
Each AIM-16 can accommodate up to 16 single-ended or differential analog inputs and contains a programmable-gain instrumentation amplifier. Amplifier gain is programmed through the RAG128. In the case of thermocouple inputs, reference junction compensation and linearization will be done as part of the host computer's application program and software routines are suppled by ACCES. For applications where watertight and/or dust-tight protection is needed, we can supply RAG128 in a NEMA 4 enclosure. Or, if 16 or 32 analog inputs are to be handled, RAG128 can be included in a RIDACS configuration and installed in a gasketed, 14-gauge steel box with stainless steel clamps on three sides of the cover and continuous heavy-gauge hinge.