Liddell Engineering LLC
Liddell Engineering LLC is a Certified UL 508A Panel Shop
We offer a full manufacturer's warranty on every Liddell Engineering installed panel.
We can...
• Design
• Fabricate
• Test
• Automate
• Program
...your custom solution. Anytime.
Liddell Engineering LLC will:
• Analyze the customer's manufacturing needs
• Consult on best solutions available to meet customer needs
• Establish equipment electrical ratings
• Develop panel design & electrical drawings
• Build custom panel(s) according to approved design
• Perform thorough QC testing and verification
• On-Site start-up and troubleshooting services
Why Do We Maintain the UL508A Listing?
The UL 508A listing for our control panel service lets you know we provide services and repairs that comply with nationally recognized safety standards. The safety of your employees and equipment is very important to us, and we assure you the electric control panels in your automation equipment are compliant with this national standard.
Holding a UL 508A listing means:
Holding a UL 508A listing means:
• We have a certification to provide inspectors and our customers with evidence that our control panels are fully compliant with national safety standards.
• Our electrical control panels are compliant with all national and local electrical codes.
• We are subject to unannounced inspections by UL personnel and periodic audits to ensure we are meeting all UL requirements at all times.
The UL Mark is one of the most recognized, accepted, and trusted symbols in the world. It shows that the Underwriter’s Laboratory has evaluated and tested samples of a component and concluded it meets UL requirements.
You also benefit from the training and consulting we receive from Underwriter’s Laboratory as we troubleshoot, repair, and maintain your control panel.
What is an Industrial Control Panel?
An industrial control panel is an assembly of components mounted on or contained in an enclosure. Alternatively, the industrial control panel may be mounted on a sub-panel. The industrial control panel unit includes the associated wiring and terminals, and can be open or closed.
An industrial control panel is made up of power circuit components, control circuit components, or a combination of both.
Power Circuit Components
• Motor Controllers
• Overload Relays
• Fused Disconnect Switches
• Circuit Breakers
Control Circuit Components
• Pushbuttons
• Pilot Lights
• Selector Switches
• Timers
• Control Relays
The industrial control panel does not include:
• Controlled Equipment
• Loads connected to power circuits
• Equipment mounted remotely from the panel and connected through wiring systems or equipment
The Liddell Engineering Control Panel Process
Liddell Engineering designs, fabricates, programs, installs, tests, and commissions each industrial control panel to your needs and specifications.
Design
Our first step is to get the basics down pat. We need to know:
• The exact type of control panel you need
• The size of the area where the panel will be installed
• The details about the site where the panel will be installed
We take pride in our attention to detail when we draw schematics, functional diagrams, and sequencing of operations. Drawings include details of the I/O and we ensure the descriptors match those in the programmable logic circuit (PLC) program.
In our control panels, we group similar voltage level devices and functions together to keep any "noisy" hardware, such as VFDs, servo amplifiers, power relays, and contactors, away from the low-level signal hardware - the controller and analog signals.
All wire sizes are coordinated for the load and components required by your equipment, and we consult with you to provide the best control type, from a simple relay to a programmable logic circuit. We also design control panel operations to match the user’s needs, from pushbuttons to a human-machine interface.
Fabrication
For efficient, reliable, and robust control panels, we use:
• Spring-cage terminals instead of standard screw terminations to reduce wiring time
• UL 1015 Tinned Nickel Copper wire for corrosion resistance
Test and Program
Before our industrial control panels leave, they are tested for appropriate operation and help you program each component to ensure efficient and accurate operation.