IPS Controllers M920 Owner's Manual page 21

M920 & M920W pH/Dual ORP Controller Owner's Manual
d. The red function LED next to Auto is illuminated.
e. pH and ORP digital displays monitor the sensor input levels.
2. pH standby
Note: While in this mode, the green pH standby LED will illuminate,
both the pH and ORP digital displays will show dashes, and all Auto
functions will be disabled. When a function pushbutton is pressed,
the corresponding digital display will show the function. Use the Up
or Down arrow buttons to the left to increase or decrease the function
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 timed
dose cycle mode, the dose LED will flash while dosing and
illuminate steadily during the delay portion of the timed
cycle. In continuous dose mode, the dose LED will flash while
dosing, and dosing will continue until pH is 0.2 below (or
above if feeding base) Set Level.
2. Selectable range: OFF, CON (continuous), and Timed
(10 – 900 seconds ON)
c. Delay Time
1. Default: Delay time of 5 minutes between feed cycles (timed
feed only). After dose time, the controller will wait (delay) for
the specified 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 timer does not automatically reset. It
must be reset by pressing the Mode button to cycle through
the Standby mode and back to the Auto mode.
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