Hach Sigma 950, Instrument Manual

Page: 93 / 146

91
Programming Features
Figure 27 Deadband Concept
B.11 Data Log
From the Main Menu, select
SETUP > ADVANCED OPTIONS > DATA LOG.
The Sigma 950 Flow Meter can record up to 115,630 readings from any or all input
channels and store them in solid state, battery-backed memory for later viewing or
retrieval.
This option selects logged input channels, the frequency of logged channels (Logging
Interval), and explains what to do when the memory becomes full.
B.12 Logging Intervals
Logging Intervals are designed to optimize the available memory so that readings can be
logged for a longer period of time. A Logging Interval is the time period over which
readings are taken and then averaged.
The Sigma 950 Flow Meter has three data logging modes; extended power mode, power
save mode, and continuous mode:
Extended Power Mode
When operating in extended power mode, the microprocessor spends most of its time
asleep, conserving battery power. Once per logging interval, the flow meter wakes up,
logs the readings from all enabled input channels, performs any other necessary duties
required, and then goes back to sleep. This mode will give the longest battery life but the
least resolution.
If you select one-minute logging interval in extended power mode, a reading will be taken
once per minute, at which time a reading is logged.
If you select a five-minute logging interval, a reading will be taken once every five
minutes, at which time that reading is logged.
Note: The Sigma 950 Flow Meter will assume it is battery operated if it measures less than 14.2
volts and dc powered in its power supply.
Power Save Mode
Power save mode is automatically initiated upon power up if a battery is installed on the
flow meter. When operating in power save mode, the microprocessor spends most of its
time asleep conserving battery power. Once per minute the flow meter wakes up, logs the
readings from all enabled input channels, performs any other necessary duties, and goes
back to sleep. This mode will give a quicker battery consumption but better resolution
with longer logging intervals.
7.60
7.40
7.20
7.00
6.80
6.60
6.40
pH
Alarm Off
Alarm On
Deadband
Low Alarm Setpoint= 6.9 pH