A request for “a panel for two pumps” describes the equipment being controlled, but leaves many decisions open. Must the pumps alternate? Run together? Maintain pressure? Fill a tank? What should happen if a sensor fails or power returns after an interruption?
A useful panel specification connects the process, electrical loads, operating sequence and installation environment. This guide explains how to organise those requirements into a request for quotation (RFQ), so proposed solutions can be compared on a clear scope.
Start With the Process, Then the Components
A component list says what equipment is proposed. A functional description says what the system needs to do. Both can be useful, but a list of a PLC, HMI and VSD does not describe the intended operation.
Write a short description in ordinary language: “Transfer water from the storage tank to the process header while maintaining the specified pressure.” Add the operating limits and conditions provided by the responsible engineering team. This gives each component a purpose.
If a consultant has already issued a specification, use it as the starting point. Identify the current revision and include its drawings and schedules. Record unresolved questions rather than quietly filling gaps with assumptions.
Distinguish the Type of Supply
An empty enclosure, a component kit and a complete wired panel are different deliverables. A replacement assembly may also need to retain existing dimensions, interfaces and functions.
State whether the enquiry covers equipment supply only, panel assembly, design, programming, testing or other work. Define responsibilities for field devices, external cabling and integration. These boundaries make quotations easier to understand and reduce the risk of expecting work that was never priced.
Explain the Operating Sequence
The sequence describes how the process moves from one condition to another. Include normal operation, manual and automatic modes, alarms, shutdown conditions and restart behaviour. “Automatic” alone does not explain any of these.
For example, a duty/standby pump arrangement needs a defined changeover rule. Alternating pumps on each start is different from changing duty after a specified running period. Starting the standby pump after a fault is another separate requirement.
Describe what operators may change and what needs restricted access. An HMI can display information and accept commands, but the application must define which actions are permitted.
Example: Make a Two-Pump Requirement Clearer
A first draft might say: “Two pumps, automatic operation, screen required.” A more useful brief separates the questions:
- Process: pressure control or tank filling?
- Duty: one pump at a time, or both under specified conditions?
- Feedback: which measurements or switches determine operation?
- Changeover: when does the standby pump take over?
- Fault response: what happens if a pump or measurement fails?
- Power restoration: what restart behaviour is permitted?
The answers must come from the application requirements and qualified assessment. This is a way to reveal the design decisions, not a ready-made control sequence for every pump station.
Build a Load Schedule
A load schedule identifies what the panel powers or controls. For motors, include the nameplate information, voltage, full-load current, duty and application. Explain starting conditions and any required speed range.
Incoming supply information belongs in a separate part of the brief. Motor ratings and supply ratings must both be confirmed. Include the supplied electrical specification and available fault-level information for assessment.
Current rating alone does not establish the suitability of distribution or protection equipment. Protection coordination, fault withstand and the starting method require technical review. If the fault information is unavailable, flag that gap.
Translate Functions Into an I/O Schedule
Inputs carry information into the controller; outputs command equipment or signal a condition. An I/O schedule identifies each point, its purpose and its electrical characteristics.
| Example point | Information to define | Why it matters |
|---|---|---|
| Pressure measurement | Range, signal type, supply and device details | The controller needs a compatible input and correct interpretation. |
| Pump-running feedback | Source and contact or signal characteristics | A start command and confirmed operation are different pieces of information. |
| Speed demand | Required interface and drive details | An analogue command and a network command need different arrangements. |
| Alarm indication | Destination and required behaviour | A local lamp, HMI message and remote notification are separate functions. |
Digital point counts do not describe every requirement. Analogue ranges, input types and communication interfaces also matter. Safety-related signals need a separate assessment rather than being treated as ordinary control points.
Define Communications and Existing Interfaces
List the equipment the panel must communicate with and the required protocols. Include complete model codes, relevant versions and available project files for replacements or upgrades.
A matching Ethernet connector does not establish that two devices exchange the required data. Protocol support, data mapping, addressing and software configuration need checking. Remote monitoring also requires a receiving system; supplying a router does not create that system automatically.
Separate hardware supply from integration, programming and commissioning. Include the responsible parties and acceptance requirements where already defined.
Specify the Environment and Physical Constraints
Record indoor or outdoor location, ambient temperature, dust, moisture, washdown, corrosion and vibration. Share the required enclosure material, ingress protection and any hazardous-area specification.
Panel size is not simply the space occupied by components. Cable bending, segregation, access, manufacturer clearances and heat management all affect the arrangement. A larger enclosure may help with layout, but does not automatically resolve cooling.
Include mounting details, available space, cable-entry requirements and access restrictions. Future spare space, spare I/O and spare electrical capacity are different allowances; specify each rather than asking for a vague percentage of “spares”.
Agree on Documentation and Acceptance
Identify required drawings, schedules, labels, manuals, software backups and final records. State which documents need approval before manufacture and how revisions will be controlled.
If factory acceptance testing (FAT) is required, define what will be tested, how results will be recorded and who will witness it. A factory functional test may use simulated field signals; it does not automatically prove the completed process operates correctly on site.
Compliance, certification and testing arrangements must be confirmed for the actual assembly and scope. The presence of individually approved components does not establish every claim about the finished panel.
Compare Quotations on the Same Scope
Two prices may cover different work. Check component models, enclosure arrangements, programming, documents, testing, delivery and exclusions before comparing totals.
Keep a short assumptions register showing what remains unresolved, who must answer it and whether it affects price or design. Agree how changes after approval will be handled. This lets an RFQ progress without disguising uncertainty as a confirmed requirement.
How Catalogue Components Fit In
Softcore Group Industrial Solutions supplies listed industrial components that may form part of an assessed panel project. A component’s website price covers that listing; a complete panel also has an assembly-specific scope.
A Practical RFQ Pack
- Process description and required operating sequence
- Load schedule, supply specification and available fault information
- I/O schedule and communications requirements
- Current drawings, equipment codes and project specifications
- Environment, mounting and cable-entry requirements
- Required approvals, documentation and acceptance tests
- Supply boundaries, unresolved assumptions, quantity, destination and required date
Existing drawings, equipment labels and a clear process description are useful starting points if a full specification is not yet available. Send an enquiry to Softcore Group Industrial Solutions at info@softcoregroup.co.za so the team can assess the requested supply and scope.
Technical Resources
Use our Technical Resources & Manuals page for documentation or assistance requesting information for the exact component.
Technical Note: This guide explains how to organise requirements. Electrical design, protection, safety functions and compliance need qualified assessment. Design, fabrication, programming, installation and commissioning are included only where expressly confirmed in the quotation.
Related Articles
- Industrial Control Panels Explained
- How to Size and Specify a Pump Control Panel
- Understanding Digital and Analogue Signals
Featured photograph: Freek Wolsink / Pexels. Illustrative stock image.