Honeywell HC900 User guide

HC900 Process & Safety Controller
Safety Manual
Doc. No.: 51-52-25-153
Revision: 1.9
Date: January 2014

ii HC900 Process & Safety Controller Safety Manual Revision 1.9
01/14
Notices and Trademarks
Copyright 2014 by Honeywell
Revision 1.9 January 2014
Warranty/Remedy
Honeywell warrants goods of its manufacture as being free of defective materials and faulty workmanship. Contact
your local sales office for warranty information. If warranted goods are returned to Honeywell during the period of
coverage, Honeywell will repair or replace without charge those items it finds defective. The foregoing is Buyer's sole
remedy and is in lieu of all other warranties, expressed or implied, including those of merchantability and
fitness for a particular purpose. Specifications may change without notice. The information we supply is believed
to be accurate and reliable as of this printing. However, we assume no responsibility for its use.
While we provide application assistance personally, through our literature and the Honeywell web site, it is up to the
customer to determine the suitability of the product in the application.
Honeywell Process Solutions
512 Virginia Drive
Fort Washington, PA 19034
Honeywell is a U.S. registered trademark of Honeywell
Other brand or product names are trademarks of their respective owners.

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About This Document
Abstract
The Safety Manual provides information about HC900 that is relevant for integration into a Safety Instrumented
System (SIS).
References
The following list identifies all documents that may be sources of reference for material discussed in this
publication.
Document Title ID #
HC900 Process & Safety Controller Installation and User guide 51-52-25-154
HC900 Process Controller Technical Overview Specification 51-52-03-31
HC900 Module Specification 51-52-03-41
Process Control Designer Specification 51-52-03-43
HC900 Process Control Designer User Guide 51-52-25-110
HC900 Process Control Utilities User Guide 51-52-25-126
HC900 Process Controller Function Block Reference Guide 51-52-25-109
HC900 Process Controller Communications User Guide 51-52-25-111
HC900 Controller Redundancy Overview & System Operation 51-52-25-133
900 Control Station For use with HC900 Process Controller 51-52-25-148
Station Designer Software manual 51-52-25-149
IEC 61508 (2010) - External document N/A
IEC 61511 (2004) External document N/A
Revision Information
Document Name Revision Number Publication Date
51-52-25-153 HC900 Process & Safety Controller Safety
Manual Revision 1.9 January 2014

iv HC900 Process & Safety Controller Safety Manual Revision 1.9
01/14
Support and Contact Information
For Europe, Asia Pacific, North and South America contact details, refer to the back page of this manual
or the appropriate Honeywell Solution Support web site:
Honeywell Organization WWW Address (URL)
Corporate
http://www.honeywell.com
Honeywell Process Solutions
www
.honeywellprocess.com
HPS Technical tips
https
://www.honeywellprocess.com/en-
US/explore/products/control
-monitoring-and-safety-
systems/scalable
-control-solutions/hc900-control-
system/Pages/hc900
-controller.aspx
Telephone and Email Contacts
Area Organization Phone Number
United States and
Canada Honeywell Inc.
1-800-343-0228 Customer Service
1-800-423-9883 Global Technical Support
Global Email Support Honeywell Process Solutions
Email: (Sales)
[e-mail]
or (TAC)
[e-mail]

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Symbol Definitions
The following table lists those symbols that may be used in this document and on the product to denote certain
conditions.
Symbol Definition
This DANGER symbol indicates an imminently hazardous situation, which,
if not avoided, will result in death or serious injury.
This WARNING symbol indicates a potentially hazardous situation, which, if
not avoided, could result in death or serious injury.
This CAUTION symbol may be present on Control Product instrumentation
and literature. If present on a product, the user must consult the
appropriate part of the accompanying product literature for more
information.
This CAUTION symbol indicates a potentially hazardous situation, which, if
not avoided, may result in property damage.
WARNING
PERSONAL INJURY: Risk of electrical shock. This symbol warns the user of a
potential shock hazard where HAZARDOUS LIVE voltages greater than 30 Vrms,
42.4 Vpeak, or 60 Vdc may be accessible. Failure to comply with these
instructions could result in death or serious injury.
ATTENTION, Electrostatic Discharge (ESD) hazards. Observe precautions for
handling electrostatic sensitive devices
CAUTION, HOT SURFACE: This symbol warns the user of potential hot surfaces
which should be handled with appropriate caution.
Protective Earth (PE) terminal. Provided for connection of the protective earth
(green or green/yellow) supply system conductor.
Functional earth terminal. Used for non-safety purposes such as noise immunity
improvement. NOTE: This connection shall be bonded to protective earth at the
source of supply in accordance with national and local electrical code requirements.
Earth Ground. Functional earth connection. NOTE: This connection shall be bonded
to Protective earth at the source of supply in accordance with national and local
electrical code requirements.
Chassis Ground. Identifies a connection to the chassis or frame of the equipment
shall be bonded to Protective Earth at the source of supply in accordance with
national and local electrical code requirements.

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Terms and Abbreviations
1oo1 One out of one
2oo3 Two out of three
Basic Safety The equipment must be designed and manufactured such that it protects against risk
of damage to persons by electrical shock and other hazards and against resulting fire
and explosion. The protection must be effective under all conditions of the nominal
operation and under single fault condition
DU Dangerous Undetected failures
FMEDA Failure Modes, Effects and Diagnostic Analysis
Functional Safety The ability of a system to carry out the actions necessary to achieve or to maintain a
defined safe state for the equipment / machinery / plant / apparatus under control of
the system
GTS Global Technical Support Center
HFT Hardware Fault Tolerance
Low demand mode Mode, where the frequency of demands for operation made on a safety-related system
is no greater than one per year and no greater than twice the proof test frequency.
PFD
AVG
Average Probability of Failure on Demand
Safety Freedom from unacceptable risk of harm
Safety Assessment The investigation to arrive at a judgment - based on evidence - of the safety achieved
by safety-related systems. Further definitions of terms used for safety techniques and
measures and the description of safety related systems are given in IEC 61508-4.
SFF Safe Failure Fraction, the fraction of the overall failure rate of a device that results in
either a safe fault or a diagnosed unsafe fault.
SIF Safety Instrumented Function, a set of equipment intended to reduce the risk due to a
specific hazard (a safety loop).
SIL Safety Integrity Level, discrete level (one out of a possible four) for specifying the
safety integrity requirements of the safety functions to be allocated to the E/E/PE
safety-related systems where Safety Integrity Level 4 has the highest level of safety
integrity and Safety Integrity Level 1 has the lowest.
SIS Safety Instrumented System – Implementation of one or more Safety Instrumented
Functions. A SIS is composed of any combination of sensor(s), logic solver(s), and
final element(s).

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Contents
The Safety Manual .......................................................................................................... 1
Scope................................................................................................................................................. 1
Basic Skills and Knowledge ................................................................................................................ 1
Safety Standards for Process & Equipment Under Control (PUC, EUC) .............................................. 1
The IEC 61508 and IEC 61511 Standards .......................................................................................... 2
Introduction ..................................................................................................................... 5
System Overview................................................................................................................................ 5
HC900 Control System Architectures.............................................................................. 9
Introduction to the Hardware............................................................................................................... 9
Non-Redundant Controller and Non-Redundant IO ........................................................................... 13
Redundant Controllers and Non-Redundant IO ................................................................................. 13
HC900 controller Features................................................................................................................ 15
Scope of SIL Certification for HC900 Control System Architectures................................................... 16
Design and Implementation of HC900 Control System ................................................. 17
Allowable Function Blocks for Process and Safety Functions ............................................................ 17
HC900 Control System Operational Modes....................................................................................... 46
Hardware and wiring requirements for safety configuration................................................................ 46
HC900 Safety configurations............................................................................................................. 48
HC900 Control System Diagnostics .................................................................................................. 52
HC900 SIL Control System communications..................................................................................... 53
HC900 system Start-up test .............................................................................................................. 54
HC900 PFD................................................................................................................... 55
Probability of Failure on Demand (PFD) for Low Demand Mode........................................................ 55
HC900 Control System Fault Detection and Response................................................. 57
Principle of Fault Detection and Response........................................................................................ 57
Diagnostic Test Interval .................................................................................................................... 57
Fault Reaction and IO states............................................................................................................. 58
HC900 Controller Diagnostics........................................................................................................... 59
HC900 SIL Compatibility................................................................................................................... 59
Reliability data............................................................................................................... 62

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Tables
Table 1 – IEC 61508 versus IEC 61511 terminology............................................................................................2
Table 2 – Descriptions of Major Components ....................................................................................................10
Table 3 – Descriptions of Major Redundancy Components.................................................................................12
Table 4 – Function Blocks .................................................................................................................................17
Table 5 – Status Indicators.................................................................................................................................52
Table 6 – SIL Levels .........................................................................................................................................55
Table 7 – Diagnostic Test Intervals....................................................................................................................57
Figures
Figure 1 – Small HC900 Controller Configuration ...............................................................................................5
Figure 2 – Expanded HC900 Controller Configuration.........................................................................................6
Figure 3 – Single process with redundancies ........................................................................................................7
Figure 4 – Configuration with Multiple Controllers..............................................................................................9
Figure 5 – Redundant Configuration with multiple I/O racks..............................................................................11
Figure 6 – Two safety applications process with redundancies (C75 CPU only)..................................................14
Figure 7 – Analog Input Voting Block ...............................................................................................................42
Figure 8 – Analog Output Validation Block .......................................................................................................43
Figure 9 – Digital Input Voting Block................................................................................................................43
Figure 10 – Digital Output Validation Block ......................................................................................................43
Figure 11 – Fault Monitor Block........................................................................................................................44
Figure 12 – IO-V function block connections....................................................................................................46
Figure 13 – Individual Series DO connections....................................................................................................47
Figure 14 – Common Series DO connections.....................................................................................................47
Figure 15 – Series Relay for Analog Outputs .....................................................................................................48
Figure 16 – Safety Dataflow ..............................................................................................................................49
Figure 17 – Sample controlled start-up configuration .........................................................................................50
Figure 18 – Sample VFAIL qualification ...........................................................................................................50

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The Safety Manual
This manual is intended for users who have Honeywell HC900 product with SIL certification and intend to
use it in SIF.
Scope
The Safety Manual provides information about HC900 that is relevant for integration into a Safety
Instrumented System (SIS). This manual is aimed at technical personnel responsible for such integration.
The Safety Manual is a reference guide providing detailed information regarding safety aspects in HC900.
A reference guide is a HC900 related guide and does not describe tasks in terms of how to perform the task
in terms of steps to follow. A reference guide can provide input to support decisions required to achieve a
certain objective.
Basic Skills and Knowledge
Before you start work on the HC900 SIS it is assumed that you are certified to do work on safety related
systems and devices, and that you have appropriate knowledge of:
• The concepts and functioning of the HC900
• The applicable process and equipment under control within the SIS,
• This Safety Manual,
• Site procedures,
• Applicable safety standards (e.g. IEC 61508 and IEC 61511)
This guide assumes that you have a basic familiarity with the process(es) connected to the equipment under
control and that you have a complete understanding of the hazard and risk analysis
Safety Standards for Process & Equipment Under Control (PUC, EUC)
Processes and Equipment Under Control (PUC/EUC) in the process industry require a high level of safety.
Safety Instrumented Systems (SIS) are used to perform Safety Instrumented Functions (SIF).
Instrumentation that is used for SIFs, must meet minimum standards and performance levels. Standards like
IEC 61508 and IEC 61511 have been developed for this purpose. One of the performance criteria that these
standards apply is the Safety Integrity Level (SIL). IEC 61508 details the design requirements for achieving
the required SIL. The safety integrity requirements for each individual safety function may differ. The
safety function and SIL requirements are derived from hazard analysis and risk assessments. The higher the
level of adapted safety integrity, the lower the likelihood of dangerous failure of the SIS, These standards
also address the safety-related sensors and final elements regardless of the technology used.
The HC900 can be used in a specific SIF that demands SIL 1 or SIL 2.
Only the HC900 portion of the EUC control system will be documented in this safety manual.
HC900 can be used only in applications for Demand mode operation.

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Safety Integrity Level (SIL)
The IEC 61508 standard specifies 4 levels of safety performance for safety functions. These are called
safety integrity levels. Safety integrity level 1 (SIL1) is the lowest level of safety integrity, and safety
integrity level 4 (SIL4) the highest level. If the level is below SIL1, the IEC 61508 and IEC 61511 do not
apply. HC900 can be used for processing multiple SIFs simultaneously demanding a SIL1 and SIL2.
The IEC 61508 and IEC 61511 Standards
SISs have been used for many years to perform safety instrumented functions e.g. in chemical,
petrochemical and gas plants. In order for instrumentation to be effectively used for safety instrumented
functions, it is essential that the instrumentation meets certain minimum standards and performance levels.
To define the characteristics, main concepts and required performance levels, standards IEC 61508 and IEC
61511 have been developed. The introduction of Safety Integrity level (SIL) is one of the results of these
standards.
This brief provides a short explanation of each standard. Detailed information regarding IEC 61508 and
61511 can be found on the IEC web site, http://www.iec.org.
What standard to use?
• If you are in the process sector and you are an owner/user, it is strongly recommended that you pay
attention to the IEC 61511 (ANSI/ISA 84.00.01).
• If you are in the process sector and you are a manufacturer, it is strongly recommended that you pay
attention to the IEC 61508.
• If you are in another sector, it is strongly recommended that you look for, and use, your sector specific
IEC standard for functional safety (if there is one). If none exists, you can use the IEC 61508 instead.
IEC 61508 and IEC 61511 terminology
This guide contains both IEC 61508 and IEC 61511 related terminology. As the IEC 61511 sits within the
framework of IEC 61508 most of the terminology used may be interchanged. Table 1 below provides an
overview of the most common interchangeable terminology.
Table 1 – IEC 61508 versus IEC 61511 terminology
IEC 61508 terminology IEC 61511 terminology
safety function safety instrumented function
electrical/electronic/programmable electronic
(E/E/PE) safety-related system
safety instrumented system (SIS)
IEC 61508, the standard for all E/E/PE safety-related systems
The IEC 61508 is called “Functional safety of electrical/electronic/programmable electronic safety-related
systems” IEC 61508 covers all safety-related systems that are electrotechnical in nature (i.e. Electrical,
Electronic and Programmable Electronic systems (E/E/PE) ).

The Safety Manual - The IEC 61508 and IEC 61511 Standards
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Generic standard
The standard is generic and is intended to provide guidance on how to develop E/E/PE safety related
devices as used in Safety Instrumented Systems (SIS). The IEC 61508:
• serves as a basis for the development of sector standards (e.g. for the machinery sector, the process
sector, the nuclear sector, etc.)
• can serve as stand-alone standard for those sectors where a sector specific standard does not exist.
SIL
IEC 61508 details the design requirements for achieving the required Safety Integrity Level (SIL). The
safety integrity requirements for each individual safety function may differ. The safety function and SIL
requirements are derived from the hazard analysis and the risk assessment. The higher the level of adapted
safety integrity, the lower the likelihood of dangerous failure of the SIS. This standard also addresses the
safety-related sensors and final elements regardless of the technology used.
IEC 61511, the standard for the process industry
The IEC 61511 is called “Functional safety - Safety instrumented systems for the process industry sector”.
It is also referred to as the ANSI/ISA 84.00.01.
This standard addresses the application of SISs for the process industries. It requires a process hazard and
risk assessment to be carried out, to enable the specification for SISs to be derived. In this standard a SIS
includes all components and subsystems necessary to carry out the safety instrumented function from
sensor(s) to final element(s). The standard is intended to lead to a high level of consistency in underlying
principles, terminology and information within the process industries. This should have both safety and
economic benefits.
The IEC 61511 sits within the framework of IEC 61508.
For more information regarding, or help on, implementing or determining, the applied safety standards for
your plant/process please contact your Honeywell affiliate.
Our Safety Consultants can help you to:
• perform a hazard risk analysis
• determine the SIL requirements
• design the Safety Instrumented System
• validate and verify the design
• train your local safety staff

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Introduction
The Honeywell HC900 Process Controller is an integrated loop and logic controller that is designed
specifically for small- and medium-scale unit operations.
System Overview
It comprises a set of hardware and software modules that can be assembled to satisfy any of a broad range
of control applications. The HC900 Controller System can consist of a single rack, as indicated in Figure 1,
or can be can be networked with other controllers via Ethernet links to expand the dimensions of process
control over a wider range of unit processes, as indicated in Figure 2 .
Figure 1 – Small HC900 Controller Configuration

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Figure 2 – Expanded HC900 Controller Configuration
The HC900 Controller design enables users and OEMs who are adept in system integration to assemble a
system that fits a broad range of requirements. Any configuration can be readily modified or expanded as
requirements dictate. In initial configuration and in subsequent modifications, the HC900 Controller affords
an optimum balance of performance and economy. Configurations such as those shown in Figure 1 and in
Figure 2, as well as many variations, can be assembled from modular components. Many of the
components are available from Honeywell, and some are available from third-party suppliers. These
modular components are available in any quantity and mix that make the most sense for a given
application. As indicated in Figure 3, the HC900 Controller includes provisions for communication via
Ethernet with host systems such as the Honeywell Experion HMI and other HMI software that supports
Ethernet Modbus/TCP protocol. Also, the communication structure of the HC900 Controller enables
remote placement of input/output components, allowing significant economies in cabling and wiring.

Introduction - System Overview
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Figure 3 – Single process with redundancies

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HC900 Control System Architectures
Refer to the following manuals for more details on the various HC900 control system architectures.
Introduction to the Hardware
The Honeywell HC900 Process Controller includes a set of hardware modules that can be combined and
configured as required for a wide range of small to medium process control applications. Some of the
modules are required in all configurations. Others are optional; they are selected as appropriate to provide
optional functions and/or to "size" the system, either in initial planning, or in modifying and/or expanding
the system to meet changing requirements. An HC900 Controller configuration with multiple controllers is
illustrated in Figure 4. This illustration includes key-numbers that identify components that are described in
Table 2. An HC900 Redundant Controller configuration with multiple I/O racks is illustrated in the below
figure.
Figure 5. This illustration includes key-numbers that identify components that are
described in Table 3.
Figure 4 – Configuration with Multiple Controllers

HC900 Control System Architectures -
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Table 2 – Descriptions of Major Components
Key No. Component
Name
Description Source
1 Controller
(Local) Rack
Includes: Rack, Power Supply, Controller Module,
and I/O modules
Honeywell
2 I/O Expansion
Rack
(C50S/C70S
CPUs only)
(Optional) Includes: Rack, Power Supply, Scanner
Module, and I/O modules
Honeywell
3 Operator
Interface
900 Control Station operator interface
communicates via Ethernet or RS-485 serial link
Honeywell
4 PC
Configuration
Tool
(Optional) PC (laptop or desktop) connects to
RS-485 or Ethernet port(s) on any (one) Controller
module. Includes Honeywell Designer Software
(configuration software).
PC & USB to RS485
convertors are from
third-party suppliers.
Configuration software
is from Honeywell.
5 HMI (Human-
Machine
Interface)
(Optional) PC link to Ethernet network, which may
include other HMIs, other HC900 Controllers, and
other networks (including Internet).
Typically includes HMI operating software.
May also include Designer Software (configuration
tool and utility software).
PC is from third-party
supplier. HMI software
is available from
Honeywell (PlantScape
or SpecView32) or
from third-party
supplier.
6 Ethernet
100Base-T
Switch
Enables connection of the private Ethernet
100Base-T port on a (C50S/C70S CPU only)
Controller Module to the (S50S) Scanner modules
on 2, 3, or 4 I/O Expansion racks. (If a single I/O
expansion rack is connected directly to a Controller
Module, the Switch is not required.)
Honeywell Qualified
Switch from Honeywell
or third- party suppliers
6a Ethernet
10/100Base-T
Switch or
Router
Enables inter-connection of several 10/100Base-T
Ethernet devices in an Ethernet network. Devices
include other HC900 Controllers, HMIs, and can
also include routers, brouters, servers, and other
devices in wider networks.
Third-party suppliers.
7 Shielded CAT5
Ethernet cable
Connects I/O expansion racks (S50S only) to
controllers (C50/C70 CPU only) and/or to
10/100baseT Ethernet switches.
Honeywell or Third-
party suppliers
Fiber Optics
Cable
Controller to remote rack distance up to 750m
(2460 ft.) with one fiber cable. Distances up to
1500m (4920 ft.) are possible with a fiber switch
used as a repeater at the midpoint.
8 Shielded CAT5
Ethernet cable
Connects devices in Ethernet Open Connectivity
network to 900 Control Stations and PC SCADA
applications.
Honeywell or Third-
party suppliers
10 RS-485 cable Shielded twisted pair cable connects Isolated
Controller port to field devices or PC with RS-485
convertor
Honeywell or Third-
party suppliers

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Redundancy
Figure 5 – Redundant Configuration with multiple I/O racks

HC900 Control System Architectures -
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Table 3 – Descriptions of Major Redundancy Components
Key No. Component
Name
Description Source
1 Controller
(Local) Rack
Includes: Rack, 2 Power Supplies, 2 C75S
Controllers, 1 Redundancy Switch Module (RSM)
Honeywell
2 I/O Expansion
Rack
Includes: 1 S75S Scanner 2 module, 1 Power
Supply, and up to 4, 8, or 12 I/O modules. Optional
second Power Supply and Power Status Module
(PSM) on 8- and 12-slot I/O racks.
Honeywell
3 Operator
Interface
900 Control Station operator interface
communicates via Ethernet or RS-485 serial link
Honeywell
4 PC
Configuration
Tool
(Optional) PC (laptop or desktop) connects to
RS-485 or Ethernet port(s) on any (one) LEAD
Controller module. Includes Honeywell Designer
Software (configuration software).
PC & USB to RS485
convertors are from
third-party suppliers.
Configuration software
is from Honeywell.
5 HMI (Human-
Machine
Interface)
(Optional) PC link to Ethernet network, which may
include other HMIs, other HC900 Controllers, and
other networks (including Internet).
Typically includes HMI operating software.
May also include Designer (configuration tool and
utility software).
PC is from third-party
supplier.
HMI software is
available from
Honeywell (PlantScape
or SpecView32) or
from third-party
supplier.
6 Ethernet
100Base-T
Switch
Required if using 2 or more I/O Expansion racks.
Provides connection of the private I/O Ethernet
100Base-T port on a (C75S) Controller Module to
the (S75S) Scanner modules. Switch not required
for connection to a single I/O rack.
Honeywell
6a Ethernet
10/100Base-T
Switch or
Router
Enables inter-connection of several 10/100Base-T
Ethernet devices in an Ethernet network. Devices
include other HC900 Controllers, HMIs, and can
also include routers, brouters, servers, and other
devices in wider networks.
Honeywell or third-
party suppliers.
7 Shielded
Ethernet CAT5
cable
Connects I/O (S75S) expansion racks to (C75S)
controllers and/or to 10/100baseT Ethernet
switches. It also connects to 900 Control Stations
and PC SCADA software applications.
Honeywell or third-
party suppliers.
Fiber Optics
Cable
Controller to remote rack distance up to 750m
(2460 ft.) with one fiber cable. Distances up to
1500m (4920 ft.) are possible with a fiber switch
used as a repeater at the midpoint.
9 RS-485 cable Shielded twisted pair cable connects Isolated
Controller port to field devices or PC with RS-485
convertor
Honeywell or Third-
party suppliers