Hach Sigma 950, Инструкция по эксплуатации инструмента

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Batteries and Chargers
We only recommend this battery for the battery box. Use of any other battery may cause
damage to the battery pack assembly and/or decreased battery life.
When to Replace the Batteries
The circuitry associated with the Alkaline Lantern Battery Pack is designed to boost the
working battery voltage to 12 V dc or higher while the alkaline batteries discharge and
expire.
As the collective voltage of the alkaline batteries begins to drop, the booster circuitry of
the Alkaline Lantern Battery Pack will begin to lose its effectiveness. As the batteries
expire, the displayed voltage will begin to drop. When the displayed voltage gets to 11 V
dc, the flashing “Low Main Battery” warning will appear on the lower right menu bar. The
logger will continue to operate down to 10.5 volts but you should replace the batteries
soon.
If the logger contains a bubbler module and/ or is operating in freezing to subzero
climates, you should consider replacing the batteries when the displayed voltage reads
12 V dc.
Factors Effecting Alkaline Lantern Battery Life
Cold Temperatures:
If the ambient temperature drops between freezing and -20 °C, the battery pack will
experience a 0 to 40% loss in life. Although this loss is extensive, as the temperature
rises to above freezing, the battery will recover with an overall minimal degradation to
battery performance. This, of course, is dependent upon the length of time the battery is
exposed to these temperatures. The Alkaline Lantern Battery Pack is not recommended
for these applications. Use of the Alkaline Battery Box in freezing or sub-zero weather
may cause a premature ‘Program Complete.’ If the voltage drops to 10.5 V dc or lower,
the meter may shut itself down and complete the program to protect stored data.
Steady Flow:
In conjunction with cold temperatures, constant flow in a seasonal climate will keep the
air temperature in the manhole around 45 °F (7° C). If the flow stops, then the ambient
temperature would tend to equalize with the temperatures experienced above the
manhole. If the outside temperature is at freezing or less, then the effects of the cold
conditions listed above may occur.
High Velocities:
Sites with velocities running at eight to twelve feet per second will tend to force the flow
meter to “stay awake” longer to take a valid velocity reading of the flow stream. To “stay
awake” means that the meter has gone from a powered down idle state, drawing only 1
mA, to being fully powered up in order to operate the circuitry involved in recording a
reading. Normally, the unit will power up for four seconds or less to take a reading. Higher
velocities cause the meter to stay on a few seconds longer before determining that the
velocity reading is valid. Essentially, the meter may actually ‘stay awake’ twice as long
per recording interval. This combined overall awake time can decrease battery life.
Improper Installation of Velocity Probes:
Any velocity probe that is installed incorrectly will cause the meter to process longer to
determine a valid velocity. The probes must be mounted level and pointed straight or
parallel in the flow stream. If possible, locate the probe in non-turbulent sites.
Improper Installation of Ultrasonic Probes:
Mount ultrasonic probes firmly and parallel with the flow stream surface. If the probe is
mounted at an angle to the flow stream, the meter will increase the gain on the signal and
wait longer for a valid ultrasonic level measurement. This will also equate to decreased
battery life.