IPS Controllers M920 Owner's Manual page 22

M920 & M920W pH/Dual ORP Controller Owner's Manual
2. The Over Timer is interlocked with the Dose Time selection.
i. If the Dose Time is set to a timed cycle, the Over Timer
will count timed feed cycles. Every time the set level is
reached the time will reset its count. If the preset cycle
is reached, the pH digital display will flash, and the pH
output relay will de-energize. The controller must be reset
manually by cycling out of and back into the Auto mode
using the mode button.
- Selectable range: 20 to 100 cycles
ii. If the Dose Time is set to a continuous feed mode, the
Over Timer will count in minutes. Default is 60 minutes.
- Selectable range: 20 to 180 minutes
3. When the Dose Time is changed from either timed or con-
tinuous feed, the Over Timer is reset to Default.
4. Turning off the Over Timer will void any NSF Certification and
is not recommended for safety reasons.
e. High Alert
1. Default: 8.0 pH
2. Selectable range: OFF, 7.5 pH to 8.4 pH (acid feed). A high
alert will occur if the pH level remains above the High Alert
level for 10 continuous minutes, and will automatically turn
off the High Alert when the pH level falls below the high alert
level for 1 continuous minute. During High Alert, the pH dose
output will be disabled, and by default ORP1 and ORP2 will
be disabled (see Dip Switch #2 settings).
f. Low Alert
1. Default: 7.0 pH
2. Selectable range: OFF, 6.8 pH to 7.4 pH (acid feed). A low
alert will occur if the pH level remains below the Low Alert
level for 10 continuous minutes, and will automatically turn
off the Low Alert when the pH level rises above the low alert
level for 1 continuous minute. During Low Alert, the pH dose
output will be disabled.
20