Wednesday, August 22, 2018

How to Turn Off and Turn On A Sunny Boy System

There are 2 disconnects on a Sunny Boy system, and maybe a third disconnecting means at the
rooftop if the design called for it, but to just shut the system down, you can ignore any possible rooftop disconnect.

The order of shutting things down is critical, because the Sunnyboy Inverter monitors the incoming utility power for Voltage and Frequency.   

As a safety, if the Voltage and Frequency are out of Standards, the Sunny Boy will go into an "Error Mode" which can be very problematic to get out of.   I don't like it, but that is the way it is.

So, it's very do-able, just follow this, print it out is even better. 

So 2 aspects:   Shutdown and Re-Start.

On shutdown, you need to turn off the DC Disconnect first.   The Sunnyboy and it's brain run on DC power.   So if you shut down the DC power, the "brain" won't be concerned when the utility AC goes down later.  

Turn off the DC disconnect first, then
Turn off the AC disconnect

On startup, you need to do the opposite.   

Turn on the AC disconnect, then
Turn on the DC disconnect.

On startup, once you turn on the DC disconnect, the Sunnyboy will first check to make sure the AC from HECO is OK and within specs.   If the HECO power is not will go into an error mode, that can be a big problem.   Then the upper light will start flashing green if all is OK so far.   

After a while, maybe 30 seconds, that light should turn solid green.   That's GOOD!   Anything else is bad, and you could retry the process, or may have to do a trouble call to PES.