A ceiling light puts the shadow of your own head right on the cutting board. Stand at almost any kitchen counter in Fairfield after dark and you can see it: the overhead fixture behind you, the cabinets above you, and a dim band of counter in between, which is where all the real work happens.

Under-cabinet lighting fixes that, and it is one of the most satisfying small jobs in a house. It is also easy to get wrong. A good share of the under-cabinet calls I take start with strips someone already installed that now flicker, buzz, or have gone dark at one end.

Hardwired or plug-in, and why it matters

Plug-in kits are sold everywhere. A strip sticks under the cabinet, a cord drops to the nearest countertop receptacle, and a small adapter on that cord converts the power. They work. But the cord hangs in plain view, it takes a receptacle you wanted for the toaster or the mixer, and that adapter is usually the cheapest part in the box.

Hardwired lighting runs from a proper circuit inside the wall to a switch you choose, with the driver hidden where it can breathe. Nothing dangles on the backsplash, nothing is plugged into the counter outlets, and the control sits by the doorway or beside the other kitchen switches. For a remodel, or for anyone planning to stay in the house for years, hardwired is the version that disappears into the kitchen and keeps working.

Plug-in still has a place in a rental or as a quick test of where light looks good. It just should not be the permanent answer in a kitchen you own.

The driver is the part nobody thinks about

LED strips cannot run on household power directly. They need a driver, a small power supply that converts 120 volts down to the low voltage the strips use, usually 12 or 24 volts. The driver decides how steady the light is, how long the system lasts, and whether it will dim at all.

A driver loaded right up to its rating runs hot, and heat is what kills LED electronics. Shut inside a closed cabinet with no airflow, it fails even sooner. I size the driver with room to spare for the total length of strip, mount it where it can shed heat and be reached later, and use one rated for where it lives.

Long runs need thought too. Voltage drops along the strip, so a long run fed from only one end goes dimmer toward the far cabinet. Feeding it from the middle, or from both ends, keeps the whole counter even.

Dimmers, drivers and the flicker people blame on bulbs

Dimming LED tape is a matched-pair problem. A driver is built to be dimmed one particular way, and the wall dimmer has to speak that same language. Put an old incandescent-style dimmer on a driver that was never designed for it and you get flicker at the low end, a buzz inside the box, or strips that never quite turn off.

The fix is choosing the dimmer and the driver together, from the manufacturers’ compatibility lists, before anything goes on the wall. On a flickering under-cabinet job, the first thing I look up is the model number of each.

Why cheap strips flicker or die early

• A driver running at the top of its rating with no room to cool.
• A dimmer that was never made for that driver.
• Long runs fed from one end, so the far cabinet goes dim.
• Strips stuck straight to wood with no aluminum channel to carry heat away.
• Loose snap connectors between sections that lose contact over time.

Where the feed for the lights comes from

A hardwired system needs a power source, and the kitchen has rules about what it can borrow. The countertop receptacle circuits are there to serve the counter, so I do not tap lighting off them. Usually the feed comes from a lighting circuit in the kitchen ceiling or a nearby wall, through a new switch box, then down into the cabinet run.

Getting cable from that switch to the cabinets is the fiddly part in a finished kitchen. I fish it through the wall behind the uppers, or route it inside the cabinet back where it will not show, and bring it out right where the driver mounts. In a kitchen being remodeled with the walls open, all of that turns simple, so if new cabinets are coming, plan the lighting before the drywall goes back.

Every splice between the house wiring and the driver sits in a junction box you can still reach, never buried behind a cabinet back or stuffed in next to the dishes. If a driver fails someday, it should come out with a screwdriver, without anyone pulling cabinets off the wall.

Laying out the run before the strip goes up

Under-cabinet light should land on the front half of the counter, where hands and knives work, so the strip goes toward the front edge of the cabinet bottom, tucked behind the trim lip if there is one. Warm or neutral white usually suits a kitchen better than the blue-white of a bargain kit, and matching the color across the whole run matters more than most people guess. A run of mismatched strips looks worse than having none.

Layout, drivers and dimmers for every kind of fixture are part of our lighting contractor work in Fairfield. If the kitchen needs a new circuit for the job, the electrical installation page for Fairfield explains that side. Call (707) 803-6332 or start on the contact page, and our Fairfield page shows the other work we handle in town.