Topic
How-To
31 guides across the knowledge base.
How to Create a PID Loop in a PLC
Set up a PID instruction from scratch: scale the PV and CV, pick the action, set the execution rate, configure limits and anti-windup, tune conservatively, and test the manual and auto transitions before it controls anything.
10 min readUpdated Sep 5, 2026
How to Add an Alarm
From a request to a working alarm: define it against the philosophy, build the condition in the PLC with deadband and delays, configure the SCADA alarm with priority and message, test it end to end, and record it in the master alarm database.
9 min readUpdated Sep 5, 2026
How to Calibrate a Pressure Transmitter
A five-point calibration with a pressure source and a reference: isolate and vent, record as-found, decide whether to adjust, trim the sensor and the output separately, verify as-left, and record it so the next calibration means something.
9 min readUpdated Sep 5, 2026
How to Diagnose a Ground Loop
Prove that a noisy or offset analog signal is a ground loop, find the second ground, and fix it the right way: remove the extra ground, isolate the signal, or correct the shield termination. With the measurements that make the diagnosis certain.
9 min readUpdated Sep 5, 2026
How to Configure a Modbus Connection
Set up a Modbus RTU or TCP link between a controller and a device: get the register map, match the physical and protocol settings, build the reads and writes, handle data types and the addressing offset, and verify with a protocol tool before trusting a value.
10 min readUpdated Sep 5, 2026
How to Diagnose a Bad Quality Tag
Trace a bad quality indication from the SCADA screen back to its source: the tag configuration, the driver and device connection, the controller tag, and the field signal, using the diagnostics each layer provides, and separate a stale value from a bad one.
8 min readUpdated Sep 5, 2026
How to Calculate a Panel SCCR
Determine the short-circuit current rating of a control panel by the UL 508A Supplement SB method: list every power circuit component, find each rating, apply published series combinations and current limiting, and mark the panel with the lowest result.
10 min readUpdated Sep 5, 2026
How to Configure a Radar Level Transmitter
Commission a non-contact radar on a wet well or tank: mount it, set the reference and range from measured elevations, map false echoes with the vessel empty, set damping and the output, and verify against a tape at two levels before the controller uses it.
9 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
How to Configure VLANs on a Control Network
Turn a zone plan into switch configuration: a VLAN per zone with its own subnet, access ports for devices, tagged trunks between switches, a native VLAN that carries nothing, a separate management VLAN, and routing between VLANs only through the firewall.
10 min readUpdated Sep 5, 2026
How to Troubleshoot an Ethernet Connection
Work an Ethernet problem one layer at a time: link light and cable, then speed, duplex, and VLAN on the switch port, then address, mask, and gateway, then the application port through the firewall. Each layer has a one-minute test that rules it in or out.
10 min readUpdated Sep 5, 2026
How to Diagnose Packet Loss
Find where and why frames are dropped: measure loss with a continuous ping, localize it hop by hop from both directions, read the port counters on the path, and match the pattern to its cause: a cable, a duplex mismatch, congestion, a loop, or a radio link.
10 min readUpdated Sep 5, 2026
How to Build a Sequencer
Build a step sequencer in a controller that will not stick, restart into the wrong step, or leave equipment half way: define the steps from the narrative, choose a step register, and test every path before the plant depends on it.
9 min readUpdated Sep 5, 2026
How to Diagnose Read and Write Communications
Diagnose a controller that cannot read from or write to a device: capture the exact request and response, classify the failure as no link, no answer, or a rejected exchange, read the error or exception code, compare with a test tool, and fix the port.
8 min readUpdated Sep 5, 2026
How to Configure Remote I/O
Add a remote I/O rack to a controller over Ethernet: plan the network and addresses, set the adapter, and prove every point and the failure behavior before the rack goes into service.
8 min readUpdated Sep 5, 2026
How to Build a Tag
Create a SCADA tag that is correct, documented, and consistent with every other tag: name it by the convention, bind it to the right controller address or name, and verify it against the live value and the I/O list before it goes on a screen.
7 min readUpdated Sep 5, 2026
How to Configure Alarms
Configure alarms in the SCADA system from the alarm list: set the source, controller-generated or evaluated in SCADA, the limits and deadband and delay, and the notification; then test each alarm end to end and review the alarm rate after the first weeks.
8 min readUpdated Sep 5, 2026
How to Trend Data
Build trends that operators use: choose the tags that tell one story per trend, set scales and time spans that show the behavior, and make ad hoc trending fast enough that an operator reaches for it before a phone call.
7 min readUpdated Sep 5, 2026
How to Configure a Historian
Set up a process historian that collects what matters and keeps it: decide the tags and their classes, set collection intervals and deadbands per class, size the storage and the retention, and hand the operators a working trend on day one.
8 min readUpdated Sep 5, 2026
How to Build Pump Graphics
Build a pump symbol and faceplate that operators can read at a glance and use without error: a symbol that shows state by shape and a muted palette with color reserved for abnormal, and a test against the high-performance HMI principles before it is deployed.
8 min readUpdated Sep 5, 2026
How to Configure Remote Access
Give operators and engineers a way into the SCADA system from outside that does not give it to anyone else: a virtual private network with multi-factor authentication terminating in a demilitarized zone, and a test that proves the path works and that the.
8 min readUpdated Sep 5, 2026
How to Troubleshoot a Flowmeter
Work a flowmeter that reads wrong, reads zero, or reads with the pipe still: confirm the pipe is full and the flow is real, check the installation against the meter requirements, and compare against an independent measurement before adjusting anything.
9 min readUpdated Sep 5, 2026
How to Select Surge Protection
Select the surge protective devices for a control panel and its field circuits: list every conductor that enters, classify its exposure, choose the device type and ratings for the power, the loops, and write it into the drawings and the I/O list.
8 min readUpdated Sep 5, 2026
How to Size an Enclosure
Size a control panel enclosure so that everything fits, cools, and can be worked on: lay out the components with their clearances and wireway, add the spare space the plant will need, and mounting before ordering.
8 min readUpdated Sep 5, 2026
How to Build Terminal Schedules
Produce the terminal schedule that lets a technician find any wire: define the strips and their numbering, list every terminal with its wire numbers, the device and the field destination, and keep it current through every change.
7 min readUpdated Sep 5, 2026
How to Design Panel Grounding
Design the grounding and bonding of a control panel and its site so that faults clear, signals are clean, and surges have a path: bond the enclosure and everything in it, and verify with measurements before the panel is energized.
8 min readUpdated Sep 5, 2026
How to Test Fiber
Test a fiber link at acceptance and at fault: inspect and clean every connector, measure end-to-end loss with a light source and power meter in both directions and at the operating wavelengths, and record everything with the fiber schedule.
8 min readUpdated Sep 5, 2026
How to Program Lead/Lag Pump Control
Build duplex pump control with alternation, failure detection, minimum run and off timers, and an operator override that survives a restart.
10 min readUpdated Aug 24, 2026
How to Size a Control Panel Power Supply
Add up the real load, account for inrush and simultaneity, add headroom, and check the heat you just added to the enclosure.
7 min readUpdated Aug 14, 2026
How to Scale a 4-20 mA Input in a PLC
Turn raw analog counts into engineering units, verify at three points, and add the validity checks that stop a failed transmitter from producing a believable number.
7 min readUpdated Aug 12, 2026
How to Test a 4-20 mA Loop
Prove a current loop end to end with a meter and a calibrator, without interrupting a process you were not authorized to interrupt.
8 min readUpdated Aug 6, 2026
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