AC Coupling causing clocks on appliances to speed up

[DSeptembre (Danielle Septembre)]

related post:

Frequency change of Multiplus2 output affects appliance

Since the weather has taken a turn for the worse I have broken out the freestanding oil fired heater. This is 10 months old. The unit works fine in normal operation. The problem is that when the batteries become fully charged the digital timer clock gains time really fast so by 6am it shows 8am (Having reset the clock the night before) I have checked and the multiplus increases the frequency of the output to regulate the fronius on the AC out. This is fine but the appliance must use the mai…