SNAP PAC Brains User’s Guide
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Chapter 1
1: Introduction
About SNAP PAC Brains
SNAP PAC brains are powerful and versatile I/O and communications processors for your SNAP PAC
System
™
. Designed primarily to work in distributed systems controlled by a SNAP PAC S-series or
R-series controller, SNAP PAC brains provide local intelligence that frees the controller for supervisory
tasks.
Two SNAP PAC brains are available: the
SNAP-PAC-EB1
and the
SNAP-PAC-EB2
. They are identical
in their functions and features except that the SNAP-PAC-EB1 provides high-speed digital functions
and analog ramping. The SNAP-PAC-EB2 does not offer high-speed digital functions or analog
ramping. For a complete list of brain features, see
I/O Processing
As an I/O processor, the SNAP PAC brain provides the local intelligence to independently handle
functions such as latching, counting, thermocouple linearization, watchdog timers, and PID loop
control. These functions continue to work on the brain even if communication with the SNAP PAC
controller is lost.
Each SNAP PAC brain mounts on a SNAP PAC rack with up to 4, 8, 12, or 16 SNAP I/O™ modules.
Each module provides from 1 to 32 I/O points, depending on the module.
SNAP PAC brains support all the SNAP I/O analog, digital, serial, and special-purpose input and
output modules available on the Opto 22 website. These modules can all be mixed on the same
mounting rack and placed in any position on the rack, to accommodate the required mix of signals
at any location.
For more information on mounting racks, see Opto 22 form #1684, the
SNAP PAC Racks Data Sheet
.
For more information on I/O modules, visit our website at www.opto22.com.
Communications
In addition to I/O processing, SNAP PAC brains communicate over a standard 10/100 Mbps Ethernet
network. Each SNAP PAC brain is equipped with two switched Ethernet network interfaces. Because
these interfaces share a single IP address and act just like an Ethernet switch, SNAP PAC brains can be
