Fiber cables are connected so that splitter/combiners
pass inbound traffic from a switch to both modules,
and pass outbound traffic from the primary module
to a switch.
Each splitter/combiner pair mounts in an assembly
that either mounts in a chassis assembly for 19-inch
racks or fastens to the DIN rail in the enclosure. The
splitter/combiner is a passive device that does not
require electrical power.
ENHANCED COMMUNICATIONS
The Foxboro Evo architecture uses an Ethernet
control network with 100 Mbps data
communications between the ZCP270s and the
Ethernet switches (see Figure 2).
The ZCP270 can also communicate with serial and
Ethernet devices, such as PLCs, via Field Device
System Integrators and FCM100Ets/FCM100Es. This
allows connection to new device interfaces without
any changes to the controller software.
ON-LINE IMAGE UPDATE
For fault-tolerant ZCP270 modules, on-line image
update replaces the executable image (operating
system) of a running ZCP270 with a newer image
without having to shut down the equipment being
controlled by the ZCP270. New product
enhancements can be brought on-line in
1.5 seconds for heavily loaded controllers; less for
lightly loaded controllers.
Because the ZCP270 contains its executable image
in internal flash memory, and has sufficient RAM to
hold a new executable image at the same time, on
line image updates are now much easier to perform.
TIME SYNCHRONIZATION, SOE, TDRA
The Foxboro Evo system supports time
synchronization using either an externally maintained
optional source of Universal Coordinated Time (UTC)
from GPS satellites or an internal source using
proprietary software. ZCP270s and their FCM100Ets
receiving time updates via the external time source
synchronize their FBMs to 1 ms. For more
information, refer to PSS 21S-1C2 B3.
Time stamping is used for alarm messages, values
sent to the historian, and the new Sequence Of
Events (SOE) and Transient Data Recorder and
Analyzer (TDRA) features.

SOE data are discrete points that are time stamped
at the FBM, optionally to 1 ms, and sent to the
workstation on a change basis. TDRA data are
analog points that are time stamped at the FBM and
sent to the workstation every 10 ms. These new
features are supported by client software in the
workstation. To support SOE and TDRA, the
FCM100Et must be installed on the same network as
the workstation collecting the data. For information
on this software, refer to PSS 21S-2B9 B4 and
PSS 21S-2B10 B4
SOFTWARE FEATURES
The ZCP270 performs regulatory, logic, timing, and
sequential control, as well as data acquisition, alarm
detection, and alarm notification. Process variables
are controlled using time-proven algorithms
(mathematical computations performing specific
functions). The algorithms are contained in functional
control blocks, which are configured by on-site
process engineers to implement the desired control
strategies. The versatility of the algorithms, coupled
with the variety of FBMs available, provides control
capabilities suited to a broad range of process
applications. Control strategies ranging from simple
feedback and cascade loops to highly sophisticated
feedforward, nonlinear, and complex characterization
control schemes are readily implemented.
The ZCP270 also provides the following features:
Infrared communications with the controller
enables you to set and read the controller
letterbug via the Letterbug Configurator.
Alarm enhancements to the function blocks:
re-alarming on changes to alarm priority,
re-alarming based upon a configurable time delay
deadband, and alarm suppression based upon
time.
Optional UTC external time synchronization.
Improved controller performance.
Optional self-hosting mode (I/A Series software
v8.4-v8.8 or Control Core Services v9.0 or later)
allows the ZCP270 to start up and run, executing
its configured control scheme using the
checkpoint file stored in flash memory. This
allows the ZCP270 to boot itself with a valid
control database even if its host workstation is
not present.
Self-Hosting Feature, Available with 200 Series
FBMs Only
The self-hosting feature is recommended only for use
in ZCP270s which are used with 200 Series FBMs.
All of the information necessary to reboot 200 Series
FBMs is included in non-volatile flash memory on the
ZCP270. However, the flash memory on the
100 Series FBMs and related products on the 268k
fieldbus does not include this information, and they
require the workstation host to be present to reboot.
More details on the self-hosting feature are available
in DIN Rail Mounted FBM Subsystem User’s Guide
(B0400FA).
DEVICES SUPPORTED
The ZCP270 with FCM100Ets supports the following
devices:
All 200 series FBMs (FBM201. FBM202. and so
forth)
Field Device Systems Integrator (FDSI) modules
Intrinsically Safe I/O Subsystem (ISCM)
DCS Fieldbus Modules for Siemens APACS+™
Systems
DCS Fieldbus Modules for Westinghouse
WDPF® Systems.
DCS Fieldbus Modules for Fisher's PROVOX®
Series 20 Migration with HART.
DCS Fieldbus Modules for Honeywell® TDC
2000 Systems with HART.
The ZCP270 with FCM100Es supports the following
devices on the 2 Mbps module Fieldbus:
All 200 Series FBMs (FBM201. FBM202. and so
forth) - both Compact or standard types