RV 220-50-SP Instructions

Thank you for purchasing the 50 Amp Hughes Autoformer. This device is designed to protect your RV from both damaging low voltage and high voltage spikes. It also lets you know if the park’s power is safe.
To use your Autoformer:

  1. Make sure the park power breaker is turned off.
  2. Plugin your Autoformer and check for a snug fit with the park receptacle.
    If this connection is not snug you may damage the plug because a loose connection will not let the current flow easily and get excessively hot. See park management.
  3. Turn on the breaker and check the LEDs on the front of the Autoformer. If lights 1 ­ 4 are green you’re good to go. If any light is red, do not plugin. Check with the park management to make sure the park is correctly wired. Each red light indicates a different park power issue.
  4. 1 ­ 4 green? Turn off the breaker. Plug the RV into the Autoformer. Switch on the breaker. Never plug the RV into a live receptacle.
  5. Your Autoformer is now monitoring the park voltage. If the voltage drops below 113 volts the Autoformer will boost to 123 volts and the line boosting light will appear. The 50 amp circuit has two 120 volt lines. Only one line may need a boost. The Autoformer will continuously boost 10%. Once the park voltage rises to 115 volts or above, the boost mode will turn off.
  6. The Autoformer is now ready to absorb any high voltage spikes that may threaten your RV appliances. In the unlikely event that all the surge capacity is used up. The green surge capacity light will turn red. When this happens, contact Hughes at 888-540-1504 for a replacement module.
  7. Happy travels and thank you for choosing Hughes.

Documents / Resources

HUGHES AUTOFORMERS RV 220-50-SP Voltage Booster with Surge Protection [pdf] Instructions
RV 220-50-SP, Voltage Booster with Surge Protection

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  1. Hughes autoformers does exactly what it says on the tin. The voltage at an RV park once dropped to 99V and sometimes didn’t go above 105V. after I first plugged this in I saw that it had a loose connection within the socket connector and also the voltage was already ramping up. The voltage before plugging within the amp was 103V but went up to 117V and 113V with the AC on. My air con motors are much happier in this manner.

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