Craver ElectricA transfer switch inspection before winter in Wake County, NC is the most reliable way to confirm your standby generator will actually deliver power when an ice storm drops the grid. Ice storms do not announce themselves politely. The ones that hit Wake County tend to arrive overnight, coat the power lines by morning, and drop whole neighborhoods off the grid for two or three days. Your transfer switch is the single component that decides whether that generator gets power into your house. If its contacts are worn, you may not know until the lights go out and the circuits are not behaving right.
Inspecting in October or early November gives you enough runway to fix whatever the inspection turns up before the first serious ice event. Wait until December, and lead times on parts can stretch.
- Transfer switch contacts wear down over time, and pitted or corroded contacts increase resistance that robs your generator of usable power right when you need it most.
- Winter ice storms in Wake County are the most demanding test a transfer switch faces, so inspecting before November is the right window to act.
- An electrician checks contact condition visually and with a low-resistance ohmmeter, looking for pitting, arc marks, and resistance readings outside acceptable range.
- A transfer switch that trips slowly or hums under load is showing symptoms worth investigating before the first hard freeze hits Raleigh, NC.
- Depending on what the inspection finds, the repair is sometimes a cleaning or contact replacement, not a full switch replacement.
#What Are Transfer Switch Contacts and Why Do They Wear?
Transfer switch contacts are the physical metal surfaces that close together to complete a circuit, either connecting your home to the utility grid or connecting it to your generator. Every time the switch operates, those surfaces touch, carry current, and then separate. That arc when they separate is small, but it is real, and it leaves a mark.
Over years of operation, those marks accumulate. The surface develops pitting, small craters where metal has vaporized and redeposited. Corrosion from humidity adds to it. In Raleigh's climate, which cycles between hot humid summers and damp winters, the inside of an outdoor or garage-mounted transfer switch enclosure sees meaningful moisture variation. That speeds the process.
A transfer switch that only operates a few times a year still ages. The contacts oxidize whether the switch trips or not. Age and environment matter as much as cycle count.
The result of pitting and oxidation is increased contact resistance. The contacts are still touching, but the connection is imperfect. Resistance that should measure in the low milliohm range climbs. Higher resistance means heat, voltage drop, and reduced power delivery under load. If your standby generator system has not been evaluated alongside your transfer switch, this is the right time to consider both.
#What Does Worn Contact Resistance Actually Do to Generator Power?
Increased contact resistance does not usually prevent a generator from running. It degrades what gets through. When your standby generator is carrying a real load, a furnace blower, a refrigerator, and a few lights, the current flowing through those contacts is substantial. Even a small amount of added resistance at that current level produces a meaningful voltage drop.
Appliances sensitive to voltage, like motors and HVAC equipment, will run hotter and work harder. A furnace that normally starts cleanly may struggle or nuisance-trip. Lights dim noticeably when the refrigerator compressor kicks on. In a severe case, the contacts can arc or overheat under sustained load.
| Contact Condition | Visual Signs | Resistance Reading | Effect on Generator Power |
|---|---|---|---|
| Good | Smooth, silver-gray surface, no pitting | Low milliohm range, consistent | Full rated power delivered cleanly |
| Moderate wear | Light pitting, minor arc marks, slight discoloration | Elevated but may still pass spec | Possible voltage sag under heavy load |
| Severely worn or pitted | Deep craters, heavy oxidation, carbon deposits | Measurably high, outside acceptable range | Significant voltage drop, heat, risk of failure under load |
#How Does an Electrician Actually Inspect Transfer Switch Contacts?
The inspection starts before the panel cover comes off. An electrician looks at the enclosure itself for signs of heat stress, rust streaks, or moisture intrusion. A water-stained enclosure tells a story before anything inside is touched.
Once the panel is de-energized and safe to open, the visual inspection of the contacts comes first. The electrician notes any pitting depth, arc marks, carbon buildup, or corrosion. Contacts on a manual transfer switch are often accessible and straightforward to examine. On an automatic transfer switch, the contact assembly may be more enclosed, but the same evaluation applies.
After the visual, a low-resistance ohmmeter, sometimes called a DLRO or micro-ohmmeter, measures actual contact resistance. The NFPA 70B Standard for Recommended Practice for Electrical Equipment Maintenance recommends transfer switch contacts be tested for resistance as part of a routine maintenance program, with readings compared against manufacturer specifications and prior baseline readings. A reading that has climbed significantly from a previous inspection, or that exceeds the manufacturer's stated limit, is a flag for action.
You cannot safely inspect the contacts directly, but you can notice symptoms. If your generator runs fine at light load but lights flicker or dim when the HVAC kicks on, mention that to an electrician. A transfer switch that makes a prolonged buzzing or hesitates during a test cycle is also worth having looked at before winter. Unexplained electrical behavior during generator operation may also point to broader electrical repair needs in the home circuit.
#Does a Worn Transfer Switch Always Need Full Replacement?
Not always. The answer depends on what the inspection actually finds. Contacts with light oxidation and minor surface marks can sometimes be cleaned and dressed with appropriate contact cleaning tools, restoring a lower resistance measurement without replacing anything. That is a legitimate repair on the right type of switch.
When pitting is deep enough that contact area is genuinely reduced, or when the contact tips on a particular switch model are below minimum thickness, replacement is the right call. On many automatic transfer switches, the contact assembly or the entire switch module is a replaceable component, not a custom fabrication. Parts availability depends on the switch manufacturer and model, which is another reason to check before you are in the middle of an outage.
A full enclosure or switch replacement is sometimes the most practical path on an older unit where the contacts are worn, the neutral bar shows corrosion, and the overall condition of the unit does not make targeted repair cost-effective. An honest inspection tells you which situation you are in.
#What Should Raleigh Homeowners Do Before November?
If your standby generator has not had a transfer switch inspection in the last few years