M920 & M920W pH/Dual ORP Controller Owner’s Manual
19
d. The red funcon LED next to Auto is illuminated.
e. pH and ORP digital displays monitor the sensor input levels.
2. pH standby
Note:Whileinthismode,thegreenpHstandbyLEDwillilluminate,
boththepHandORPdigitaldisplayswillshowdashes,andallAuto
funconswillbedisabled.Whenafunconpushbuonispressed,
thecorrespondingdigitaldisplaywillshowthefuncon.UsetheUp
orDownarrowbuonstotheletoincreaseordecreasethefuncon
value.
a. Set Level
1. Default: 7.4 pH
2. Selectable range: 7.0 – 8.0 pH (in 0.1 increments)
b. Dose Time
1. Default: Timed dose of 10-second pH feed relay energized
and 5 minutes pH feed relay de-energized. In the med
dose cycle mode, the dose LED will ash while dosing and
illuminate steadily during the delay poron of the med
cycle. In connuous dose mode, the dose LED will ash while
dosing, and dosing will connue unl pH is 0.2 below (or
above if feeding base) Set Level.
2. Selectable range: OFF, CON (connuous), and Timed
(10 – 900 seconds ON)
c. Delay Time
1. Default: Delay me of 5 minutes between feed cycles (med
feed only). Aer dose me, the controller will wait (delay) for
the specied minutes before checking the current level and
dosing again if necessary.
2. Selectable range: 1 - 99 minutes.
d. Over Timer
1. Default: ON. The over mer does not automacally reset. It
must be reset by pressing the Mode buon to cycle through
the Standby mode and back to the Auto mode.