Hi All,
I started going down this road when I connected my camper to my Champion 5500 inverter generator. It has a 30A RV receptacle which I connect my camper to (also having the 30A connection, its a Wildwood FSX 167RBK). The issue is when the compressor in the AC unit kicks on (13,500 BTU) it trips the 110 outlets in the camper.
I saw a lot of recommendations for the
Micro-Air EasyStart Breeze AC Soft Starter and started doing research on them. During my searches I found
"Plug and Play" Soft Starters that you plug into the generator and it also acts as a surge protector as well. I've seen mixed reviews on their ability to perform the function and also their longevity which gives me a bit of pause.
Does anyone have any experience and can recommend if the simpler plug and play would actually work? Also if I am barking up the wrong tree on what would help with my outlet tripping please let me know that too.
Thanks so much for reading and hopefully offering some input.
Hey Amjet, you may have solved your problem already but for anyone that comes along, this info may be helpful. I'll try not to be verbose, but details are important.
The reason softstart devices are helpful is to provide a 'jolt' of extra power for a second or two to help start the compressor. This is needed due to the in-rush of high amperage for most inductive motors at the first seconds of start up. An AC compressor is simply a motor in a sealed refrigerant system. You can see this start-up amperage spike using an ammeter clamped around any of the 3 wires of the compressor circuit (it must be analogue type meter, digital meters don't show this spike very well). Ironically we called them 'hard-start kits' back in the 80's, but I digress.
Before installing a soft start device, which is basically a start-capacity with a relay switch, you may want to check some things in your RV that will contribute to hi-amp startups. Thus eliminating the need for a startup device. Please note: Ive not considered the best order of these items to troubleshoot, as the order may be different depending on circumstance.
Check all 120v wiring in the AC unit on the roof. FIRST! cut off the breaker to disable power to the AC, remove the cover to AC, check with a meter if you have one just to make sure the power is off. Or,
unplug shore power! Then, look at all 120v wiring connections carefully. Including circuit boards, spaid clips at circuit boards, wire-nut connections and look for 'browning, darkening, corrosion or loose connections, a connection of any type that is slightly loose will cause dramatically higher amperage thru the circuit at that of the connection point.
Another place Ive found bad or burnt connections was at the compressor terminals. To check, remove the small terminal block cover (usually on top of the compressor) where the incoming wires feed the compressor, this will expose the terminal block. Check for browning, corrosion or loose spaid clips, or once I found the 'high-temp' cut-out switch to have dirty contacts. This switch is in-line to the common leg of the 3 compressor wires and located under the terminal cap. The switch is sealed, replace it if bad. Using and ohm-meter can help diagnose the condition of this switch. In some compressors, this switch will be integrated in the motor not field serviceable.
Another culprit, look at the motor capacitor(s), if it's swollen around its body, or on the top surface where wires attach, or has oil leaking from it, this indicates a failing or failed capacitor. This significantly increases high startup amps and a softstart device WILL NOT FIX this problem. You must replace the capacitor (very easy to do). Typically they cost $10-$15 on amazon. Check the specs printed on the capacitor body to get a matched replacement. Do not mismatch the capacitor specs or you may damage your compressor. Many RV roof units have a dual capacitor, meaning one physical capacitor actually has two combined into one body. It provides capacitance for both the compressor and fan motor. Some AC units will have a separate capacitor for the compressor and one for the fan mtr. Again, take pictures to ensure you rewire correctly if you need to replace one.
A dirty condenser coil can cause a higher startup amps due to the system running hot, which will make the compressor work harder, also decreasing cooling capacity. Look up on YT how to clean both your condenser and evaporator coils. Your AC will run much better and last years longer if you do this. Remember, there is no filter to clean the air flowing thru the condenser coil, it's all outside unfiltered airflow. An AC unit 4 years old or more is usually going to have dirty coils.
Low line voltage. If your line voltage coming into your rooftop AC is low, say 110-115, you'll have higher startup amps. This line voltage will drop further once under a load.
Also, check shore power voltage. If you have a volt meter, test the incoming voltage (with no loads) for example, remove the plug from your RV and test the voltage at the Plug (carefully not get shocked) you should have 118-122v. Anything below 115v would concern me, because after you apply all your RV loads, that 115v may drop to 112v or lower - no good! Call your camp office if your getting low line voltage at the shore power.
A bad breaker can cause higher-amp problems, or the wire coming from the output of the breaker may be loose, if so, clean the bare copper wire, reinstall and tighten it well!
This is not all things possible to contribute to hi-amp start ups, but these are common in my experience. Im sure others will chime in to add other reasons. Lastly, I'll say that I believe in the benefits of startup kits, I think it can prolong the life of motors, start contacts and even run-capacitors, by reducing heat in the motor circuit, especially motor windings.
I hope these tips are helpful to someone.
