8 Best RV Surge Protectors For 50 Amp (September 2026) Complete Guide

A 50 amp RV surge protector is a device that sits between your coach’s power cord and the campground pedestal. It absorbs voltage spikes through metal oxide varistors, and the better models go further: they analyze the pedestal wiring before you connect, then watch voltage continuously and cut power when conditions turn unsafe. For a rig running 50 amp service, it is the cheapest insurance you can bolt to the outside of the coach.

Here is the part most shopping guides get wrong. Lightning is the dramatic failure, and it is not the common one. What actually cooks an air conditioner compressor, a refrigerator control board or a converter is a brownout at 105 volts, an open neutral where one of the two hot legs drops out, or a pedestal that somebody wired backwards months ago. Forum owners have said for years that the pedestal is the weakest link in the whole chain, and reading the iRV2 and r/RVLiving threads makes it obvious why a circuit analyzer matters as much as a joule number.

That is what separates a good list of the best 50 amp RV surge protectors from a bad one. Joule ratings across this category run from 1650 to 18000, which sounds decisive but tells you very little on its own, because a protector that only lights a red LED for an open neutral leaves your rig plugged into bad power. We spent weeks reading spec sheets, owner reviews and forum threads on the eight units below, then ranked them on the two things that decide the outcome: whether the device cuts power, and whether the brand has a decade of field history behind it.

We also pulled in what to do when the fault is the campground’s fault, not yours, and where a 30 amp adapter changes the math. If you are still working out whether a home surge protector belongs anywhere near this, our general RV surge protector guide covers the shorter version first.

Top 3 Picks for 50 Amp RV Surge Protectors in 2026

Our best overall pick is the Progressive Industries SSP-50XL, the most proven 50 amp protector on the market by owner count. Best value goes to the Southwire Surge Guard 44270, which pairs a 4200-joule capacity with a 4.8 average and a four-pin 50 amp format. Premium pick is the Power Watchdog PWD50EPOH, the only unit here that physically disconnects your rig and reports amperage on both legs over Bluetooth.

Why 50 Amp Is Different: 240V Split-Phase Power Explained

A 50 amp RV does not run on 120 volts. It runs on 240 volt split-phase power, which is two hot legs of roughly 120 volts each, plus a neutral and a ground, arriving through a four-pin NEMA 14-50R plug. A 30 amp rig runs on a single 120 volt hot leg through a three-pin TT-30P plug. That difference is the reason a 30 amp protector can never be used on a 50 amp coach: the extra leg carries current the device was never built to monitor.

Both legs matter, and a good 50 amp protector diagnoses them separately. The CARMTEK unit in this roundup, for example, flags lost leg on either side as well as a reversed L1 to L2 and a reversed L1 to ground, rather than collapsing everything into one generic fault light. Most cheaper analyzers only tell you that something is wrong, which is still useful, but it does not tell the campground operator whether to repair the pedestal or the service.

The practical consequence of split-phase is a voltage window rather than a single number. Both legs should sit between roughly 208 and 240 volts, and a quality EMS disconnects below about 190 or above about 250 and waits for the reading to hold steady before reconnecting. The Camco unit in our list uses per-leg thresholds of above 132 volts and below 102 volts on the 120 volt legs, which is the same idea expressed at the appliance side of the transformer.

Split-phase also changes the failure mode worth worrying about. If one leg opens, a 120 volt appliance on the surviving leg can see a voltage swing that a single-leg device simply never samples, and a compressor that browns out repeatedly is what turns into a two-thousand-dollar replacement rather than a nuisance trip.

Why Choose an EMS Over a Basic Surge Protector?

The two categories are sold side by side in the same search results, and they are not the same product. A basic surge protector clamps spikes and lights indicators. An electrical management system, or EMS, monitors voltage in real time and physically opens the relay to disconnect your rig, then reconnects on its own once conditions are safe and stable for a set period.

• Brownouts damage more than lightning. Sustained low voltage stresses compressor motors, and motors are what fail quietly and expensively.
• An open neutral is a wiring fault, not a power fault. A basic protector cannot see it. An EMS sees it and waits while you move sites.
• Reverse polarity on a miswired pedestal can be reported by an inexpensive analyzer, but only an EMS will refuse to energize the coach in the first place.
• Auto reconnect saves a 6 am departure. You do not have to stand in the rain resetting anything after a short low-voltage event.

The honest counterpoint is that most faults at a pedestal are wiring errors rather than voltage events, and a good analyzer catches those cheaply. Forum consensus splits on whether a full EMS is needed, which is why five of our eight picks are analyzers with surge protection built in, and why we rank the two true cut-power units at the top and near the top rather than sweeping every other option off the list.

All 8 Picks at a Glance in 2026

1. Progressive Industries SSP-50XL (50-Amp) – The Proven Lifetime-Warranty Choice

The Progressive SSP-50XL is the unit we recommend to almost everyone, and the reason is boring and reliable: it has more owner history behind it than anything else on this list. It holds a 4.7 average across more than 4500 ratings, and the rating distribution is unusually flat, with 85 percent five-star and only 2 percent one-star. That is the shape of a product that simply does what it says for a long time.

It is built for 50 amp service at 120 to 240 volts with 12000 W capacity, and it weighs 3 pounds in a Lexan housing measuring 14 inches long. The all-weather shield assembly and thermal protection are genuine, not marketing language, and the LED indicators are readable in low light, which matters when you are crouching at a pedestal at dusk.

What it does not do is interrupt power. The SSP line reports over and under voltage, open ground, open neutral, reverse polarity and surge failure, and that is where it stops. If a pedestal drops to 104 volts for ten minutes, this unit keeps your compressors running the whole time. That is a real limitation and the reason this is not a cut-power unit.

The lifetime warranty is the detail that flips it for us, with the weather shield excluded, which is honest since the cover does take the abuse. Progressive owners on the RV forums consistently single out USA manufacture and that warranty as the deciding quality factors, and this model also carries AC frequency protection for 50 amp systems.

Best For First-Time and Full-Timer Owners

This is the pick if you want one device that will outlast your current ownership cycle and never needs thinking about. Buy it, run it, read the LEDs before you plug in, and move on to something else. The 1650 joule figure looks unimpressive next to the 18000J units here, but joules matter most against direct strikes, and this one is built by a manufacturer that has been doing it for decades.

It also works as a second layer. A few owners in the Forest River threads run a hardwired EMS in the bay and a portable protector at the pedestal, and the SSP-50XL is the natural portable half of that pairing because it is cheap, heavy enough to feel solid, and covered for the life of the rig.

Where It Falls Short

Skip it if you camp at older parks where brownouts are common and you want power cut automatically rather than flagged. The weather cover will not close fully over a cord with a pull handle, and the 14-inch body is awkward on stacked pedestal outlets, which is the layout at a lot of older campgrounds.

Also skip it if you need to know the actual voltage numerically. There is no display, only indicator lights, so you learn the pedestal is bad but not how bad. For that, one of the smart units below gives you a reading in your pocket.

2. Southwire Surge Guard 44270 (50-Amp) – The Best Value Analyzer

The Southwire Surge Guard 44270 is the value pick, and a 4.8 average across more than 3300 ratings is an unusual number for anything in this category. Southwire is also one of the three brands that forum owners treat as default-safe, alongside Hughes Autoformers and Progressive Industries, which is not something a spec sheet can tell you.

It carries 4200 joules of surge protection, which is more than double the Progressive above and the highest capacity among the indicator-style units we reviewed. More importantly, it analyzes the circuit before you energize the coach and lights indicators for open ground, open neutral and correct polarity, so you can walk away from a bad pedestal before plugging anything in.

Southwire is the only Big Three brand in this roundup that stayed in the pure analyzer tier, and that shows up in the owner reports: the recurring praise is for the diagnostic LEDs and the joule figure, and the recurring limitation is that it diagnoses rather than interrupts. Owners on the Forest River forums who run the higher-spec 34950 describe it saving a rig from low voltage twice and an open neutral once, which is a different class of device from this one.

The body is a 22.25 inch plug-in rectangle in black and yellow, with no app, no display and nothing to install. You plug it into the pedestal and plug the coach into it, which is the whole procedure.

Best For Weekend Campers and Older Parks

This is the right buy if you camp a handful of times a year, mostly at established campgrounds, and your main worry is connecting to a pedestal somebody wired wrong. The analyzer does that job well, the LEDs are easy to read, and there is no firmware, no pairing and no phone to charge.

It also suits owners who are replacing a failed cheap protector and want the brand-recognition tier without moving up to a hardwired installation. r/GoRVing owners repeatedly steer new campers toward one of the Big Three, and this is the cheapest honest way to do that.

Where It Falls Short

The one-year warranty is the shortest in this group, and that matters more than it sounds, because a surge protector is a sacrificial device and a long strike can end the warranty conversation. If you camp in exposed or coastal sites, the 4200 joule figure is thin against repeated smaller events.

It also will not help you at all with a sustained low-voltage event, since it has no relay to open. If your parks are known for brownouts, step up to the Camco or the Power Watchdog rather than expecting this one to intervene.

3. Power Watchdog PWD50EPOH (50-Amp) – The Only True Disconnect Unit Here

The Power Watchdog PWD50EPOH is the most capable device in this roundup and the only one that actually opens the circuit. Emergency Power Off cuts power on extreme voltage fluctuation and restores it once the condition resolves, which is the entire difference between knowing about a fault and being protected from it. It carries 6100 joules and a 4.7 average across more than 2600 ratings.

It is hardwired inside the coach rather than plugged in at the pedestal, and that single design choice solves the two most common RV protector complaints at once. There is nothing left at the pedestal to steal, and nothing exposed to rain, ice or salt air. The tradeoff is installation, which needs someone who can wire a 50 amp circuit correctly.

Bluetooth monitoring through the phone app shows voltage and per-leg amperage, which is the closest thing here to seeing the split-phase balance in real time. The surge module is replaceable, so a strike does not mean buying a whole new unit, and owners report manufacturer support sending replacements, including after a documented lightning strike that destroyed the device but left the coach intact.

That history is why the most repeated advice in the RV forum threads is simply to buy the best Power Watchdog you can afford, with the EPO variant called out specifically. The standing objection in those same threads is that the unit is the one people worry about catching fire, which in practice traces back to installation quality and cord handling rather than the device itself.

Best For Full-Timers With Dual Air Conditioning

Choose this if you run two air conditioners, live in the coach year round, or camp in places with unreliable pedestals. A Class A motorhome pulling 50 amps is exactly the load profile where a brownout does real compressor damage, and this is the only unit in our list that responds by disconnecting rather than by lighting an LED.

It is also the right pick as the bay layer in a two-layer setup, paired with a portable analyzer at the pedestal for a second opinion on the site before you energize. One owner converted from a portable EPO model to a hardwired unit and preferred the permanence, which matches how most of the long-term owners in those threads describe it.

Where It Falls Short

Bluetooth only, with WiFi monitoring sold as a separate module, so remote checking means being within range of the coach. The app reports error codes without explaining what they mean, some owners read the voltage about 6 volts low against an external meter, and the status LED is bright enough to be a problem in a dark cab.

There is also no bypass for nuisance shutdowns at parks with chronically low voltage, and the supplied wiring documentation has been reported as inconsistent with the diagram for the hardwired model. Have the installer confirm orientation before the panel goes back together.

4. MILLIONHOME 50 Amp (50-Amp) – The Highest Joule Rating We Reviewed

The MILLIONHOME 50 amp protector carries an 18000 joule rating, the highest capacity in this group, and it does it in a 3.94-inch cube that weighs 1.5 pounds. That is an unusual amount of surge absorption in a very small package, and it holds a 4.8 average across 969 ratings with 87 percent at five stars.

It works as a plug-and-play adapter, which is the format most owners in this category want: adapter into the pedestal, RV cord into the adapter. The circuit analyzer reports wiring status before connection, so the sequence is check the lights, then energize.

Build quality reads better than the generic high-joule units usually do. The housing is flame-retardant and waterproof for outdoor conditions, and several owners describe the feel as a step up from cheaper adapters. The honest caveat, and one owners raise themselves, is that most buyers have never actually taken a surge, so the protection performance is largely untested by the people rating it.

Forum owners are skeptical of high joule figures on unfamiliar brands, and that skepticism is not silly. A large number is not a substitute for certification, and a 4200-joule unit from a manufacturer with a decade of field history may be the safer bet in a real strike. What the number does buy you is headroom against repeated smaller events at an exposed site.

Best For Exposed and Lightning-Prone Sites

If you camp in open ground, at a coastal park or in a region with frequent summer storms, capacity is the argument. This unit simply holds more than the certified legacy brands here, and the waterproof housing means you can leave it connected through heavy rain without thinking about it.

It is also the easiest unit here to carry, at 1.5 pounds in a cube that fits a storage bay, so owners moving between sites will actually take it with them rather than leaving it behind.

Where It Falls Short

It is an indicator, not an EMS. Nothing disconnects, so a brownout runs to completion while you watch a light. There is no numeric readout either, only LEDs, so you cannot log voltage across a stay.

The most repeated complaint is a clear plastic face cover that detached shortly after arrival. Owners consistently praise responsive support, but the cover is a consumable part of the face rather than a sealed housing, and there is no stated warranty period in the listing.

5. Camco Power Grip 55306 (50-Amp) – Auto Disconnect Without an App

Camco is a long-established RV brand, and the Power Grip 55306 is the mid-way option between a plain analyzer and a full smart EMS. It protects against high voltage above 132 volts and low voltage below 102 volts, disconnects automatically from dangerous conditions, and reconnects when normal operation resumes. No app, no account, no Bluetooth pairing.

That auto reconnect is the feature that changes daily life. Owners in the RV threads describe leaving a coach plugged in overnight at a park with intermittent power and coming back to a running rig instead of a tripped breaker and a walk to the pedestal in the dark.

Diagnostic LEDs flag reverse polarity, open neutral and other wiring issues at connection, and the NEMA 14-50P to 14-50R configuration is a straightforward plug-in with no wiring. The contoured Power Grip handles exist because the unit weighs 6.8 pounds, which is the heaviest item we reviewed and genuinely awkward on a crowded pedestal.

Its 4.5 average is the lowest in this group, and the 7 percent share of one-star reviews explains why. Joule capacity of 4200 is modest next to the 15000 to 18000 J units, the warranty is limited to one year, and the review base of 671 is on the smaller side for a device this heavy.

Best for Owners Who Hate Apps

This is the pick if you want a protector that makes decisions on its own and you have no interest in monitoring anything from your phone. It does exactly one job, does it without connectivity, and the LEDs tell you after the fact what tripped it.

It also suits owners whose parks have unstable power but whose rig is not at high risk, since a Class B or a mid-size trailer on a 50 amp site will not draw enough to stress a compressor the way a dual-air-conditioner coach does.

Where It Falls Short

Weight is the practical issue. At 6.8 pounds, on a stacked pedestal with two neighbouring rigs, handling it in the rain is genuinely unpleasant, and the weatherproof rating applies when it is installed upright.

The one-year warranty and the modest 4200 joule figure are the two reasons this is not higher. If you camp in lightning country or coastal salt air, the corrosion exposure on a heavy plastic body is worth thinking about, and a higher-rated unit with a longer warranty is the better bet.

6. FOCSPROD 50 Amp (50-Amp) – The Most Surge Capacity Per Dollar

The FOCSPROD 50 amp unit is the budget pick, and it is the least expensive thing in this roundup by a wide margin while still claiming 16000 joules of surge protection. It holds a 4.8 average across 709 ratings, with 86 percent at five stars and 2 percent at one star, which is a strong showing for a newer listing.

Its analyzer is more detailed than most of the cheap tier. It distinguishes power on, open ground, open neutral, neutral reversed, over or under voltage, and no power, displayed on a clear red and green indicator panel, so you get six states rather than a single fault light.

The right-angle 50 amp plug with power grip handles is a nice touch that reduces cord strain, and several owners mention running it through lightning storms or on 38-foot campers without incident. The waterproof cover is reported to hold up in heavy rain and Florida weather, which is a fair test of a Florida summer.

What you are giving up is history. The review base is short, the customer support commitment is stated as three years rather than a product warranty, and much of the feedback is brief. As one group of owners puts it on these products generally, most have not yet had an actual surge to test against, so the capacity number is unproven in the field.

Best for First-Time Owners on a Budget

If this is your first 50 amp protector and you want real circuit diagnostics without spending much, this is the sensible entry point. The six fault states cover the wiring mistakes that actually occur at campground pedestals, which is where nearly all the risk lives.

It is also a good second unit to keep in the storage bay, since a portable protector that lives in the coach gets used and one that lives at home does not. Owners upgrading from a 30 amp adapter report continuity in build quality, which is a reasonable durability signal.

Where It Falls Short

Nothing disconnects. If the park puts out 105 volts for an hour, this unit blinks and keeps your appliances running through it, which is the exact scenario the better units exist to prevent.

There is also no numeric voltage reading, no replaceable surge module, and a shorter review history than the Big Three brands. In a high-stakes install, buy a brand with a decade of service history instead.

7. GEARGO 50 Amp (50-Amp) – The IP68 Pick for Coastal and Wet Sites

The GEARGO 50 amp protector pairs 15000 joules of surge protection with an IP68 sealing rating, and that combination is the reason it is on this list. IP68 is the highest ingress rating in the group, which is the number that matters if you camp on the coast, in the mountains or through a wet shoulder season. It holds a 4.8 average across 534 ratings, and it ranks first in RV plugs, inlets and receptacles.

The circuit analyzer identifies correct wiring, open ground, open neutral, reverse polarity, reverse neutral or ground, and no power, which puts it alongside the CARMTEK in diagnostic granularity. The right-angle male plug is designed for easy connection and disconnection, and the heavy-duty metal anti-theft tab accepts a cable lock, which answers one of the recurring owner worries about portable units.

Long-standing owners of the 30 amp version vouch for the brand and report the 50 amp model keeps the same solid feel while adding capacity, which is a useful continuity signal for a relatively young listing. The manufacturer support is described as responsive, and the enclosure is a rugged, flame-retardant design intended to reduce fire risk from circuit faults.

Like most of this category, it shows faults and leaves the decision to you. There is no relay, so a low-voltage event does not disconnect anything, and the most consistent complaint in the reviews is that the documentation does not explain how to reset a tripped unit and there is no reset button.

Best for Salt Air, Rain and Long Seasons

If your camping life involves salt, standing water, freezing nights or a full season parked outdoors, sealing is the spec that pays off. An IP68 enclosure keeps water out of the housing where cheaper units eventually corrode at the contacts, and the three-year warranty gives you a replacement path that the one-year units here do not.

The anti-theft tab is a small detail that solves a real problem, since portable protectors left at a pedestal are a recurring worry in owner threads. Pair it with a cable lock and the theft question mostly goes away.

Where It Falls Short

It cannot disconnect, so it is the wrong choice for a park with chronic brownouts. The missing reset instructions are more annoying than they sound, because a unit that has latched a fault and will not tell you how to clear it is frustrating at a dark pedestal.

At 3.21 pounds in a 10 by 7 by 6 inch body it is also not the most compact, and 534 ratings is a thinner history than the three brands forum owners treat as safe defaults.

8. CARMTEK 50 Amp (50-Amp) – The Most Detailed Per-Leg Diagnostics

The CARMTEK 50 amp unit is the one to buy if your concern is telling the campground exactly what is wrong with their pedestal. Its diagnostic chart covers correct wiring, open ground, open neutral, L1 or L2 open, L1 to L2 neutral reversed, L1 to L2 ground reversed, and open circuit or no power, which is the most granular per-leg reporting of any indicator unit we reviewed.

That granularity is the whole point on a split-phase system. When an owner can report that L2 is open rather than that something is wrong, the park can fix it in one visit instead of swapping components at random.

It is UL tested and built from flame-retardant material, weather resistant and thermally protected for outdoor use, rated 50 amps at 125 to 250 volts on 50 and 60 Hz through a NEMA 14-50P to 14-50R connection. The operating range of -35C to +110C is the widest we saw, which matters in desert summers and alpine nights alike.

The lifetime warranty is the longest coverage offered in this group, and forum owners treat a lifetime warranty as a decisive quality signal precisely because a surge protector is a sacrificial device. At 4200 joules it is not a capacity leader, and the review base of 357 is the smallest here, so we are relying on specification and warranty rather than a deep body of owner reports.

Best for Repeat Visitors to the Same Campground

If you return to the same park, or if your rig is your full-time home and you are the one dealing with the office manager, per-leg fault reporting pays for itself quickly. You can hand someone a specific fault code instead of a description of a problem.

The lifetime warranty also makes this the lowest-friction long-term option, since you do not have to think about replacement timing or track a warranty expiry. The wide temperature rating suits owners who camp in extreme climates.

Where It Falls Short

Like most of the analyzer tier, it shows faults and never intervenes, so a sustained low-voltage event runs to completion with your appliances connected. The 4200 joule rating is the weakest claim in a category that now advertises 15000 and 18000.

And with 357 ratings, it has the least owner history of the eight, so we would pair it with a second layer at the pedestal rather than trust it alone. For a full-time coach in a lightning-prone region, the hardwired Power Watchdog remains the more defensible long-term choice.

Which 50 Amp Protector Fits How You Camp

Read the list above first, then route yourself. A full-timer with dual air conditioning in an exposed park wants the Power Watchdog PWD50EPOH hardwired, with a portable analyzer at the pedestal as a second layer, which is the configuration experienced owners in the Forest River and r/GoRVing threads describe most often.

Coastal and alpine campers should look at sealing first, which puts GEARGO at the front of the queue given the IP68 rating. Lightning-prone and open-site campers are trading capacity against brand history, and MILLIONHOME leads on the 18000 joule figure while the Progressive SSP-50XL leads on warranty and field record.

Weekend campers at established parks want the least maintenance, which is the Southwire 44270 with no app and nothing to wire. First-time owners on a budget get real fault coverage from the FOCSPROD unit, and anyone who refuses to touch an app but still wants power cut lands on the Camco Power Grip. Owners who mostly deal with miswired pedestals rather than surges want the CARMTEK chart.

How to Choose a 50 Amp RV Surge Protector

Decide whether you need an EMS or an analyzer first. If your risk is a miswired pedestal, an analyzer with per-leg fault detection solves it. If your risk is sustained low voltage, or you run heavy loads like two air conditioners, only an EMS disconnects. No amount of joules substitutes for a relay.

Use these joule thresholds. Treat 3000 joules as the floor for a 50 amp rig and think of 4000 to 6000 as the comfortable middle. Above 10000 joules makes sense for exposed, coastal or lightning-prone sites where repeated smaller events are likely, which is why the MILLIONHOME and FOCSPROD units sit where they do.

Check the plug before you buy anything. A 50 amp rig uses a four-pin NEMA 14-50R and a 240 volt split-phase supply. A 30 amp rig uses a three-pin TT-30P on a single 120 volt leg. A 30 amp protector must never be used on a 50 amp rig, because the unmonitored leg will not be protected at all. Going the other direction is fine with a dogbone adapter, and the adapter goes into the pedestal with your RV cord into the adapter.

Read the IP rating for where you camp. IP65 handles rain, IP67 allows temporary submersion and IP68 is the deepest sealing in this group. For home or garage storage on a 110 volt outlet you also want a unit that will tolerate being coiled up wet, and a unit with a replaceable surge module is worth more than extra joules over a ten-year ownership.

Know what not to put on the circuit. A 50 amp pedestal is sized for an RV, not a workshop. Space heaters, hair dryers, welders, portable air compressors and other non-RV high-draw appliances should never share the RV circuit, because a single overload event on a shared pedestal defeats the protection you just paid for. Our home surge protector picks cover protecting the house instead.

Factor warranty into the real cost. A surge protector is a sacrificial device, and a unit with a one-year warranty that is replaced every few years costs more over a decade of ownership than a lifetime-warranty unit bought once. If your parks are older, our whole house surge protector guide covers the permanent installation equivalent for the stick-and-brick home you return to.

Maintain it. Unplug it, rinse salt and mud off the contacts, dry it fully, and keep the face free of standing water. If you run a 50 amp circuit at a property, our 50 amp EV charger picks cover the same 50 amp service from the other direction.

Frequently Asked Questions

The Best 50 Amp RV Surge Protectors to Buy in 2026

Our overall pick remains the Progressive Industries SSP-50XL, because a lifetime warranty, USA manufacture and more than 4500 owner ratings in support is a combination nothing else on this list matches. It is the first 50 amp protector we would put in a new coach, and it is the portable half of the two-layer setup experienced owners run.

Buy the Southwire Surge Guard 44270 if you want the best analyzer for the least money, the Power Watchdog PWD50EPOH if you need real disconnection and app monitoring, MILLIONHOME or FOCSPROD if surge capacity at exposed sites is the priority, GEARGO if you camp in salt and rain, CARMTEK if you want per-leg fault reporting and a lifetime warranty, and the Camco Power Grip if you want auto reconnect and no app.

Whichever you choose, read the indicator lights before you energize the coach, and never put a 30 amp protector on a 50 amp rig.