Technical Manual

Table Of Contents
7
1. Introduction
1.1. About the A733
The A733 Remote Telemetry Unit (RTU) is a portable low-power, medium-range te-
lemetry device capable of sampling up to 12 analog and 8 digital inputs (of which 4
are counter types); in addition, it can control up to 4 outputs. A 3-volt CMOS serial
interface is also built-in, allowing for configuration, data download, or expansion
(e.g. various bus implementations). The unit is based on a powerful 8-bit Flash RISC
microcontroller, which can also be programmed in the field (for software upgrades).
The units incorporates an A431 radio module operating in the 430 to 470 MHz
range, making it adaptable to most radio communication regulations in the world.
The output power is 0.5 W, while the modulation is narrow band FM (12.5, 20 or 25
kHz channel spacing).
Due to its construction, as well as to the software controlling it, the power consump-
tion is extremely low (average 1 mA—without sensors). The unit operates from a
built-in NiCd 6.2 Volt rechargeable battery, which is charged using either a solar
panel or an external power supply adapter. A special configuration may be imple-
mented where no internal battery is used, rather the power is obtained exclusively
over an external connector.
The A733 is a ruggedized unit, complying with the IP65 environmental protection
class (NEMA 4). It can be easily installed and it integrates perfectly with an Adcon
A730 network.
This manual describes the technical details of the A733, both hardware and soft-
ware. It is organized in several parts, as follows: