Regal 53 SC Owner's Manual page 146

Macerator (Overboard Discharge Pump)
MACERATOR
ON BUTTON
KEY SWITCH
MACERATOR
BREAKER
MACERATOR
seacock is opened and the macerator is activated through
a key switch and button located at the ship's main salon
control panel (shown above). At that point waste travels
from the waste holding tank through the macerator pump
where it is ground up and then exits through the hull
bottom at the open seacock.
The optional macerator
(overboard discharge pump)
is located in the engine
room. It is connected to a
normally closed interlock
type of seacock. In locals
where it is approved the
Theory Of Interlock Valve
HANDLE IN
CLOSED
POSITION
INTERLOCK
SEACOCK
ground up by the discharge pump.
To explain another way when the macerator is energized,
the valve receives the signal to open but will not supply
power to the macerator pump until fully open. This pre-
vents the hoses and head plumbing systems from being
pressurized and potentially bursting hoses or causing the
holding tank to discharge via the waste vent fi tting.
When the monitor key switch is deactivated the macera-
tor stops pumping waste and the interlock valve receives
a signal to close. It closes automatically thus eliminating
the need to crawl into the engine room to turn a manual
seacock off and to secure it shut with tie wraps.
94
Chapter 4
As mentioned previously,
there is a special mac-
erator interlock valve to
pump waste overboard
on vessels with the mac-
erator discharge option.
The interlock valve is a
type of valve which mag-
netically through a sealed
unit opens the valve
when energized by the
macerator monitor panel
key switch allows waste
to pump through the
hull bottom after being