Industrial Instrumentation & Controls: PLC, DCS, SCADA, Field Instruments & Fiber Optic
The I&C Scope From Loop Checks to SCADA Commissioning
Instrumentation and controls work begins before a single device is wired and ends after the control system has been proven to operate the facility as designed. Between those two points lies a defined sequence of work: field device installation, wiring and termination, loop documentation, loop checks, pre-functional testing, functional testing, and commissioning sign-off.
Wikota Electrical Services manages the full I&C scope for industrial and energy projects across all 48 contiguous states. The team coordinates with in-house engineering through Mid-America Services, which means instrument specifications, control panel designs, and loop diagrams are produced and maintained within the same project team that executes the field work.
Field Instrumentation and Loop Checks
Field instruments include pressure transmitters, flow meters, temperature elements, level instruments, control valves, and analytical devices. Wikota Electrical Services installs, wires, and terminates field instrumentation to instrument index and loop diagram specifications. Loop checks verify that each field device communicates correctly with the control system input and that the signal is calibrated within the specified range before commissioning begins.
PLC, DCS, and SCADA Installation
Programmable logic controllers, distributed control systems, and SCADA platforms are the command layer of industrial automation. Wikota Electrical Services performs the physical installation and field wiring of PLC and DCS panels, remote I/O cabinets, operator workstations, and network hardware. Field installation is distinct from control system programming and configuration, which is coordinated with the engineering team or the owner’s system integrator.
Fiber Optic and Industrial Networking
Industrial communication networks are increasingly fiber-based due to the immunity to electrical interference required in high-voltage environments. Wikota Electrical Services installs, splices, and tests fiber optic cable for industrial Ethernet, SCADA communication, and control system backbone networks. Testing includes OTDR testing and insertion loss measurement to verify link performance before the network is commissioned.
Fire and Gas Detection Systems
Fire and gas detection systems protect personnel and assets in facilities handling flammable or toxic materials. Wikota Electrical Services installs combustible gas detectors, hydrogen sulfide detectors, smoke and heat detectors, and manual call points. System integration with the facility’s fire alarm control panel and ESD system is included in commissioning scope.
Custody Transfer and Metering Skids
Custody transfer metering measures the quantity and quality of a product at the point where ownership changes hands. The accuracy of that measurement has direct financial consequences. Wikota Electrical Services installs and calibrates metering skids including flow computers, transmitters, samplers, and associated instrumentation to API and AGA standards. Calibration documentation is provided as part of the handover package.
Calibration and Commissioning Support
Calibration confirms that each instrument performs within its specified accuracy range under operating conditions. Wikota Electrical Services performs instrument calibration using traceable standards and provides loop calibration records for each tagged device. Commissioning support includes pre-functional checks, functional testing, and punchlist resolution through to system acceptance.
Integrated I&C and Engineering
I&C work executed with in-house engineering produces a more reliable installation. Instrument specifications are written with field installation requirements in mind. Loop diagrams reflect actual termination points. Panel drawings are produced by the same team that builds and wires the panels. When field conditions require a change, the loop drawing gets updated in the shared document system rather than marked up on a paper copy.
Frequently Asked Questions
A programmable logic controller is typically used for discrete control applications such as motor starters, valve actuators, and safety interlocks. A distributed control system is designed for continuous process control applications such as flow, pressure, temperature, and level regulation across a large number of field devices. In practice, modern facilities often use both systems, with PLCs handling discrete logic and safety functions and a DCS managing continuous process variables.
A loop check is the verification that a field instrument is correctly wired, calibrated, and communicating with the control system. The process involves applying a known input at the field device, confirming the signal appears at the correct controller input at the expected value, and verifying that any associated outputs respond correctly. Loop checks are performed before commissioning begins and documented in loop check records for each tagged instrument.
A custody transfer metering skid measures the volume or mass of a product at the point where it transfers from one party to another, such as from a producer to a pipeline or from a pipeline to a utility. Because custody transfer measurements have direct financial and regulatory implications, they must be installed and calibrated to applicable API or AGA standards and verified with traceable calibration equipment. Calibration records are required documentation for regulatory compliance and commercial agreements.
Fiber optic cable transmits data as light rather than electrical current, which makes it immune to electromagnetic interference from motors, VFDs, switchgear, and other electrical equipment common in industrial environments. Fiber also supports longer cable runs without signal degradation and eliminates the ground loop issues that can affect copper networks in facilities with multiple grounding points. The tradeoff is that fiber requires specialized splicing equipment and testing tools and cannot carry electrical power.
Fire and gas detection systems must be installed in compliance with NFPA 72 for fire alarm systems and applicable codes for gas detection depending on the type of hazard. Devices installed in classified hazardous areas must be listed for the appropriate Division or Zone classification. Functional testing and system commissioning must be performed in accordance with the manufacturer's requirements and the project specification, with testing documentation retained as part of the facility's fire protection records.