6
IM620-1
General Description
The MicroTech® Absorption Gateway (MAG) is a microprocessor-based controller used as a read-
only interface between a MicroTech absorption chiller and a MicroTech or Open Protocol partner’s
building automation system (BAS). No control of the absorption chiller is performed through the
MAG.
A MAG is needed for each absorption chiller in a network. If there is only one absorption chiller, a
single MAG can connect to the Open Protocol partner’s integrator, or stand alone as its own network.
This type of configuration is called the Direct Connect MAG. If there are two or more absorption
chillers, a level-1 controller such as a Network Master Panel (MicroTech) or an Open Protocol Master
Panel (Open Protocol) is needed to read and store information from the chillers. This type of
configuration is called the Network Connect MAG.
The base panel is equipped with eight AC power rated relays plus the necessary hardware to support
the addition of accessories listed in Table 2. For more information on the MAG accessories, see the
“Accessories” section in this manual.
Table 2. MAG Accessories
Accessories
Function
Analog Output Expansion Module (AOX-4)
Adds analog outputs
Solid-State Relay Kit (SSR)
Adds digital outputs
Component Data
Figure 1 shows the control panel layout for the MAG. The main components of the controller are the
Microprocessor Control Board (MCB), the Output Board (OB) and the Input Conditioning Module
(ICM) Terminal Board. All of these major components are mounted inside a standard NEMA 1
enclosure. They are interconnected by ribbon cables, shielded multi-conductor cables, or discrete
wiring. Power for the system is provided through transformers T1 and T2.
Following are descriptions of these MicroTech components and their input and output devices.
