Topic
Documentation
81 guides across the knowledge base.
Program Organization
Structuring a controller program so that someone else can maintain it: a layout that follows the plant, one routine per job, standard device blocks, I/O mapped in one place, a fixed execution order, naming that means something, and comments that say why.
10 min readUpdated Sep 5, 2026
The Alarm Philosophy
The document that decides what is allowed to be an alarm: the definition, the criteria, the priorities and their meaning, the performance targets, the handling rules, and who owns it. Under ISA-18.2 it comes first.
9 min readUpdated Sep 5, 2026
Alarm Rationalization
The meeting where every alarm earns its place: who attends, what is decided for each alarm, how to document it in a master alarm database, and how to run it at a utility that cannot spare a week.
10 min readUpdated Sep 5, 2026
Historian Architecture
How process history is collected, stored, and served: the collector, the archive, and the client layers, where the historian sits relative to SCADA and the DMZ, single-server and tiered designs for a utility, the store-and-forward buffer that survives outages, and the sizing that decides how many years fit on a disk.
9 min readUpdated Sep 5, 2026
Historian Data Collection
Deciding what the historian stores and how often: polled versus exception collection, the deadband per tag, rates for control loops, levels, totals, and compliance values, timestamps at the source, quality codes, calculated tags, and the tag list review that keeps a historian from filling with noise and missing what matters.
9 min readUpdated Sep 5, 2026
Reporting from the Historian
Turning history into the reports a utility must produce: the monthly operating report, compliance reports for the regulator, daily operator summaries, pump run and energy reports, the calculations behind daily minimums, maximums, and totals, handling bad quality and gaps, and building reports once so they run every month without an engineer.
9 min readUpdated Sep 5, 2026
SCADA Servers
What the servers in a SCADA system do and what a utility should expect of them: the I/O, alarm, historian, and client roles, physical versus virtual, redundancy, sizing, placement, backup, patching, licensing, and monitoring.
10 min readUpdated Sep 5, 2026
SCADA Clients
The workstations, browsers, and mobile devices operators use to see and control the system: thick, thin, web, and mobile clients, roles and permissions, where control is allowed from, workstation design, session policy, licensing, and failover behavior.
9 min readUpdated Sep 5, 2026
Trending
Using historian trends to understand a process and diagnose a problem: pens that belong together, scaling and time ranges, raw versus averaged data and what compression hides, overlays and cursors, event markers, and the patterns that point at each cause.
9 min readUpdated Sep 5, 2026
Server Failure
How SCADA servers fail and what to do when one does: failure modes from a full disk to a dead hypervisor host, what the plant experiences with and without redundancy, the recovery sequence from restore to alarm verification, and the monitoring that warns.
9 min readUpdated Sep 5, 2026
Client Problems
Diagnosing the operator station rather than the system: a client that will not connect, shows nothing, runs slowly, freezes, or stays silent on an alarm, with the causes, the order of checks, and the standard build and spare that make the fix a swap.
8 min readUpdated Sep 5, 2026
Historian Problems
How a historian goes wrong and how to find each fault: gaps, wrong values, detail never stored, disks that fill, slow queries, backfill that never arrives, and unreadable archives, with the collector, queue, configuration, and storage checks that locate it.
9 min readUpdated Sep 5, 2026
Long-Term Storage
Keeping historian data for years: a retention policy by data class that follows the record rules, tiered storage from online to offline copies, downsampling, archive management, exports that outlive the historian, and the annual proof that old data reads.
9 min readUpdated Sep 5, 2026
SQL Integration
Connecting SCADA and historian data to relational databases: why a utility does it, the methods, a schema that handles time series, the query patterns for totals and reports, the mistakes that flood a database or stall a server, and security.
10 min readUpdated Sep 5, 2026
Loop Checks
Proving every I/O point end to end before a system goes live: what a loop check is and is not, the three-point analog check, discrete and output checks, the two-person method with the sheet that records it, what to do with a point that fails, and why a loop check is not a calibration.
9 min readUpdated Sep 5, 2026
Calibration Procedures
How a utility calibrates its instruments consistently: the as-found and as-left discipline, tolerance from the loop rather than the data sheet, the reference standard and its traceability, the five-point check with hysteresis, adjusting only when needed, intervals set from history, and the procedure written once per instrument type.
9 min readUpdated Sep 5, 2026
Calibration Documentation
The records a calibration program produces and what each is for: the calibration certificate per event, the instrument history, the reference standard file, the schedule, the tolerance and interval register, and how the records are organized so a regulator, an auditor, or the next technician can find what they need.
8 min readUpdated Sep 5, 2026
Pressure Calibration
What calibrating a pressure transmitter means: as-found and as-left, the five-point test and hysteresis, tolerance and the reference standard, sensor trim versus output trim versus reranging on a smart transmitter, gauge versus absolute, and intervals.
10 min readUpdated Sep 5, 2026
PLC Program Backups
What a complete controller backup contains, how often to take one, where to keep it, why the upload from the running controller is not the master, and the verification that turns a folder of files into a recovery plan.
9 min readUpdated Sep 5, 2026
What to Back Up in a Control System
What a utility must be able to restore after a failure or attack: controller programs and firmware, SCADA and historian, HMI panels, drive and instrument parameters, network configurations, licenses, installers, and documentation, and how often each changes.
10 min readUpdated Sep 5, 2026
OT Incident Response Plan
The plan for the day the control system is not trusted: who decides, the triggers, the first hour, isolating without stopping treatment, running by hand, preserving evidence, who to notify and when, recovery from backups, and the exercise that makes it real.
10 min readUpdated Sep 5, 2026
Firewall Rule Design
Writing the rule set for a control network boundary: default deny, one rule per conduit with its reason, hosts not subnets, protocol and port and function, direction and initiator, logging on every rule, and the review that removes forgotten rules.
9 min readUpdated Sep 5, 2026
Controller Program Integrity
Knowing that the program in the controller is the one that was approved: checksums and change counters, the scheduled compare against the trusted backup, signed and protected projects, what an unexplained difference means, and making the check routine.
8 min readUpdated Sep 5, 2026
Server Hardening
Reducing what an attacker can do with a SCADA server: a baseline from the vendor guide and a benchmark, unused services removed, the host firewall on, application allowlisting, controlled media, separate administrator accounts, and logs sent off the box.
10 min readUpdated Sep 5, 2026
User Accounts and Roles
Who can do what on the SCADA and how it is enforced: roles from view-only to administrator and their permission matrix, individual accounts including the operator console, service and vendor accounts, same-day offboarding, and the quarterly review.
9 min readUpdated Sep 5, 2026
Patch Management
Applying updates to SCADA servers and clients without breaking the plant: vendor qualification, a monthly cycle with a test system, priority from the exposed edge inward, backups and rollback, emergency patches, and handling software that cannot be patched.
9 min readUpdated Sep 5, 2026
Historian Security
The historian is the most connected server in a control system and the most exposed: giving the office, reports, and the cloud the data they need without a path to the plant, with a collector in the control zone, a replica in the DMZ, and one-way flow.
9 min readUpdated Sep 5, 2026
Third-Party Software
Everything on a control system machine that is not the SCADA: drivers, databases, runtimes, reporting tools, agents, remote support utilities. Why each is an attack surface, the inventory and approved list, rules for installs, and removing what is unused.
8 min readUpdated Sep 5, 2026
Shared Account Problems
Why the shared operator login, the vendor account everyone knows, and the single PLC password are the weakest point in most utilities: no accountability, no offboarding, no detection. Containing what cannot be avoided and migrating the rest.
8 min readUpdated Sep 5, 2026
Password Policy for OT
A password policy that fits a control system rather than an office: length over complexity, rotation on events, screening against breached lists, multi-factor authentication, no lockouts that take control from an operator, and unique vaulted device passwords.
8 min readUpdated Sep 5, 2026
Credential Storage
Where the passwords and keys of a control system are kept: a vault with individual access and a log, break-glass copies in a safe, platform credential stores for service accounts, and the places they must not be, from spreadsheets to project files.
8 min readUpdated Sep 5, 2026
Security Program Basics
What a control system security program is for a utility that has never had one: a named owner, an inventory, a risk assessment, a few policies, baseline controls, training, vendor rules, an exercised incident plan, and a first-year plan for a small staff.
10 min readUpdated Sep 5, 2026
SCADA Backups
What a SCADA backup must contain to bring a system back: the project export, an image of each server, the databases, historian archives, licenses, certificates, scripts, and network device configurations, with frequency, retention, and the restore procedure.
9 min readUpdated Sep 5, 2026
Backup Testing
Why backups that have never been restored fail when needed, and how to find out: spot restores, full restores of a server to an isolated machine, controller program restores to a spare, archive reads, timing each one, and the findings and record that follow.
8 min readUpdated Sep 5, 2026
Offline Copies
The backup copy that survives ransomware: why anything reachable over the network will be encrypted too, what offline and immutable mean, options from rotated drives to immutable storage, what goes in the offline set, and the restore test that uses it.
8 min readUpdated Sep 5, 2026
Configuration Baselines
A known-good record of how every part of the control system is configured, captured at acceptance and kept current through change management: what to baseline, how to capture and store it, how to compare on a schedule, and what an unexplained difference means.
8 min readUpdated Sep 5, 2026
Change Management for OT
A change process sized for a utility control system: what counts as a change, the request with risk and rollback, owner approval, the window, backup before and verification after, the baseline update, the emergency path, and the record.
9 min readUpdated Sep 5, 2026
Isolating a Compromised System
Cutting a compromised machine, segment, or site off from the control system without stopping the process: who may decide, isolation points planned in advance, disconnecting the network rather than the power, running on manual control, and preserving evidence.
9 min readUpdated Sep 5, 2026
Manual Operation Procedures
Written procedures for running the plant and the remote sites without the SCADA or the controllers: what to read and set by hand, how often to check, what to log, chemical dosing from a flow reading, when to stop, staffing, and the drill that proves them.
9 min readUpdated Sep 5, 2026
Recovery and Restoration
Bringing a control system back after a compromise without reintroducing it: controllers verified against baselines first, servers rebuilt from clean media and project exports, every credential changed, hardening, staged reconnection, and end-to-end tests.
9 min readUpdated Sep 5, 2026
Reporting Requirements
Who a water or wastewater utility must tell about a cyber incident, how fast, and what to say: the federal critical infrastructure reporting rule, state laws, the drinking water regulator, public notification, law enforcement, the sector center, and insurers.
9 min readUpdated Sep 5, 2026
Building an OT Asset Inventory
The list of everything in the control system with a network interface or a program, and how to build one that is right: what counts, the fields to record, the site walk, the switch tables and passive listening that find the rest, and keeping it current.
9 min readUpdated Sep 5, 2026
Passive Discovery
Finding out what is on a control network by listening rather than probing: why active scans are risky around older controllers, how a mirror port feeds a sensor, what the traffic reveals, the blind spots, and how the sensor becomes continuous monitoring.
8 min readUpdated Sep 5, 2026
Documenting Firmware Versions
Why the firmware version of every controller, module, drive, switch, radio, and instrument belongs in the inventory with the date it was read: advisories are issued by version. Where to read each one, the several versions one controller has, and the cadence.
8 min readUpdated Sep 5, 2026
Advisories and Alerts
Where a utility learns its equipment has a known vulnerability and what to do with the news: the government and vendor advisory feeds, the sector center, the exploited catalog, subscribing by product, a weekly triage on exposure and consequence, and records.
8 min readUpdated Sep 5, 2026
Risk-Based Patching
Deciding what to patch first when everything cannot be patched at once: priority from exposure, exploitation, and consequence rather than scores, tiers with timelines, different rules for servers, network gear, and controllers, and the written accept decision.
8 min readUpdated Sep 5, 2026
Compensating Controls
What to do about a vulnerability that cannot be patched now or ever: restricting who can reach it, disabling the service, blocking dangerous protocol functions, allowlisting, monitoring, physical and procedural controls, matched to the attack path.
8 min readUpdated Sep 5, 2026
AWIA Requirements
What the 2018 water infrastructure act requires of community water systems: a risk and resilience assessment and an emergency response plan, certified on a schedule by size and repeated every five years, with cybersecurity named in both, and who is covered.
9 min readUpdated Sep 5, 2026
EPA Guidance
What the federal environmental agency provides to water and wastewater utilities on cybersecurity and what it expects: the free assessment, the checklist aligned with federal goals, joint incident response guidance, the enforcement position, and how to use it.
8 min readUpdated Sep 5, 2026
CISA Resources
What the federal cybersecurity agency provides to utilities without charge: the performance goals, regional advisors, external vulnerability scanning, control system advisories, the exploited catalog, a self-assessment tool, exercises, and incident reporting.
8 min readUpdated Sep 5, 2026
Multi-Factor Authentication
Requiring a second proof of identity beyond a password, where it matters most in a control system and how to do it without locking an operator out: the factor types, where it is mandatory, where it does not fit, enrollment and recovery, and vendor accounts.
8 min readUpdated Sep 5, 2026
Session Logging
Recording every remote session into the control system: who connected, from where, when, to what, and what they did, from the VPN log through jump host session recording to the SCADA audit trail and controller change log, stored off the systems and reviewed.
8 min readUpdated Sep 5, 2026
Firewall Logging and Review
Making the firewall log useful: logging on every rule including sensitive permits, sending logs to a collector off the firewall, what denials and unexpected permits mean, a weekly review a small utility can sustain, and the alerts worth waking someone for.
8 min readUpdated Sep 5, 2026
How to Assign IP Addresses on a Control Network
Build an addressing plan before the first device is configured: one subnet per zone and site, a fixed block layout so an address says what the device is, static addresses on everything that controls a process, and a schedule that is kept current.
9 min readUpdated Sep 5, 2026
Duplicate IP Address
Two devices claiming one address: a controller that answers sometimes, a workstation that reports a conflict, a ping returning from two hardware addresses. Where duplicates come from, finding both in the switch address table, and the discipline that stops it.
7 min readUpdated Sep 5, 2026
How to Read a P&ID
What a piping and instrumentation diagram shows, how ISA-5.1 tag bubbles and line types encode the control system, and how to trace a loop across sheets.
8 min readUpdated Sep 5, 2026
Control Narratives
What a control narrative is, what it must contain, how to write statements that can be tested, and how it drives programming, FAT, and the owner’s acceptance.
9 min readUpdated Sep 5, 2026
Sequences of Operation
Writing the ordered, step-by-step description of what a system does: states, transitions, timeouts, and the format that lets a programmer implement it and a tester verify it without interpretation.
8 min readUpdated Sep 5, 2026
Cause and Effect Matrices
The table that lists every trip condition against every action it causes: how to build one, what goes in the cells, how it distinguishes hardwired from software protection, and how it becomes the test.
7 min readUpdated Sep 5, 2026
Factory Acceptance Testing
Testing a control system before it leaves the shop: what must exist before the test, how the procedure is built from the narrative and the matrix, how the field is simulated, what is witnessed, and what the punch list and the sign-off mean.
9 min readUpdated Sep 5, 2026
Site Acceptance Testing
Proving the installed system with the real field: loop checks first, then end-to-end I/O, real communications, sequences on real equipment, alarms to real recipients, and failure modes on the real network, with the record that becomes the as-built.
8 min readUpdated Sep 5, 2026
I/O Lists
The document that ties the field to the controller: what every I/O list column means, how tags, terminals, and module channels are assigned, spare capacity rules, how the list drives the drawings and the program, and how to keep it true after commissioning.
9 min readUpdated Sep 5, 2026
Instrument Lists
The index of every measuring and final control device on a project: what the instrument list records, how it grows from the P&ID into specification sheets and calibration records, the columns that matter at each stage, and how it becomes the asset register the utility maintains.
8 min readUpdated Sep 5, 2026
Control Schematics
The ladder-style drawing of every control circuit in a panel: how a schematic is organized by line number, the conventions for contacts, coils, and cross-references, what belongs on a schematic and what belongs on a wiring diagram, and reading one under pressure.
9 min readUpdated Sep 5, 2026
Commissioning Checklist
From energization to handover: the sequence of commissioning activities for a control system, the prerequisites and records for each, who signs what, and the checklist that keeps a project from being declared finished while half of it has never been tested.
10 min readUpdated Sep 5, 2026
ISA Standards for Controls
The International Society of Automation standards a controls practitioner meets: ISA-5.1 symbols and tags, ISA-18.2 alarm management, ISA-101 HMI design, ISA-88 and ISA-95 for batch and enterprise integration, ISA-99 which became IEC 62443, ISA-20 specification forms, and how each is used on a water or wastewater project.
8 min readUpdated Sep 5, 2026
Wiring Diagrams
The drawing that says where every wire goes: panel wiring and interconnection diagrams, and the conventions of wire numbers, conductor colors, terminal numbers, and cable numbers that make them readable. What belongs here versus on the schematic.
9 min readUpdated Sep 5, 2026
Network Drawings
The two drawings every control network needs: a logical drawing of zones, subnets, VLANs, firewalls, and conduits, and a physical drawing of switches, ports, cables, fiber, radios, and sites. What each shows and why they are sensitive.
9 min readUpdated Sep 5, 2026
Panel Layouts
The drawing of what goes where inside a control panel: enclosure, back plate with every component to scale and keyed to the bill of material, wireways, terminals, door devices, and entries. The conventions, the required spacings, and the checks.
9 min readUpdated Sep 5, 2026
Cable Schedules
The list of every cable with what it is, where it runs, and where it lands: the columns, the numbering convention, types and signal classes, routes through conduits and trays, lengths, terminations, spares, and status from design through as-built.
8 min readUpdated Sep 5, 2026
Fiber Schedules
The record of every fiber strand between every pair of patch panels: cable identifiers, strand numbers and the standard color sequence, fiber type, connectors, what each strand carries, splices, lengths, and test results, with the labeling that matches it.
8 min readUpdated Sep 5, 2026
Network Schedules
The tables behind the network drawings: the address schedule of every device, the switch port schedule of every port, the VLAN table, and the conduit list of what the firewalls permit. How they are built, kept as the single source of truth, and protected.
8 min readUpdated Sep 5, 2026
Functional Descriptions
The system-level document that states what a control system does, organized from the overview down to each piece of equipment in one format: modes, control, setpoints, permissives, interlocks, alarms, sequences, and failure behavior, and how it is used.
10 min readUpdated Sep 5, 2026
Design Checklist
A review checklist for a control system design at each stage from concept to issued for construction: documents, architecture, controllers and I/O, panels and power, instruments, networks and security, SCADA and alarms, deliverables, and commissioning.
11 min readUpdated Sep 5, 2026
Startup Checklist
The checklist for bringing a control system and its process into operation after commissioning or an outage: verification of power, I/O, communications, setpoints, forces, and backups; staged energization; manual first, then automatic; and the watch.
8 min readUpdated Sep 5, 2026
Calibration Checklist
The checklist for one calibration event, from work order to the sticker on the instrument: notify operations, loop in manual, alarms inhibited, the reference standard, as-found, adjustment, as-left, the loop check, restoration, and the record.
8 min readUpdated Sep 5, 2026
Troubleshooting Checklist
A general checklist for any control system problem, usable at 2 a.m.: define the problem, ask what changed, make the process safe, gather the evidence before touching anything, divide the chain, change one thing at a time, restore, and record.
8 min readUpdated Sep 5, 2026
NIST Publications for Control Systems
The National Institute of Standards and Technology documents a control engineer will meet: the Cybersecurity Framework, the operational technology security guide, the control catalog, the digital identity guideline, and the incident handling guide.
9 min readUpdated Sep 5, 2026
CISA Guidance as a Reference
How the federal cybersecurity agency publications serve as reference standards for a utility: the performance goals as a baseline for policy and procurement, the water sector goals, secure-by-design principles for vendors, and the advisories.
8 min readUpdated Sep 5, 2026
EPA Rules and Their Control System Implications
The federal environmental agency rules that shape what a water or wastewater control system must measure, record, and report: the surface water rules, residual and byproduct rules, groundwater and lead rules, discharge permits, and record retention.
10 min readUpdated Sep 5, 2026
AWWA Standards and Manuals
What the American Water Works Association publishes that a control engineer uses: the instrumentation and control manual, the risk and resilience standard behind the act assessments, the security and emergency standards, and the cybersecurity tool.
8 min readUpdated Sep 5, 2026
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