Campbell CR3000 Micrologger, Руководство оператора

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Section 7. Installation
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The CR3000 is internally protected against accidental polarity reversal on the
power inputs.
The CR3000 has a modest-input power requirement. For example, in low-power
applications, it can operate for several months on non-rechargeable batteries.
Power systems for longer-term remote applications typically consist of a charging
source, a charge controller, and a rechargeable battery. When ac line power is
available, a Vac-to-Vac or Vac-to-Vdc wall adapter, a peripheral charging
regulator, and a rechargeable battery can be used to construct a UPS (un-
interruptible power supply).
Caution Voltage levels at the 12V and switched SW12 terminals, and pin
8 on the CS I/O port, are tied closely to the voltage levels of the main
power supply. For example, if the power received at the POWER IN 12V
and G terminals is 16 Vdc, the 12V and SW12 terminals, and pin 8 on
the CS I/O port, will supply 16 Vdc to a connected peripheral. If the
connected peripheral or sensor is not designed for that voltage level, it
may be damaged.
7.2.1 CR3000 Power Requirement
The CR3000 operates with power from 10 to 16 Vdc applied at the POWER IN
terminals of the green connector on the face of the wiring panel, or at the power
input receptacle on the underside of the CR3000 module, which is reserved for
interated power supplies.The CR3000 is often provided with a power supply
integrated into its base. These integrated power supplies connect to the underside
of the datalogger module. If an integrated supply is provided, the POWER IN
connector will probably not be used. If an integrated supply is not provided, an
external supply will be required.
The CR3000 is internally protected against accidental polarity reversal on the
power inputs. A transient voltage suppressor (TVS) diode at the POWER IN 12V
terminals provides protection from intermittent high voltages by clamping these
transients to within the range of 19 to 21 V. Sustained input voltages in excess of
19 V, can damage the TVS diode.
7.2.2 Calculating Power Consumption
System operating time for batteries can be determined by dividing the battery
capacity (ampere-hours) by the average system current drain (amperes). The
CR3000 typically has a quiescent current drain of 0.2 mA (with display off) 0.3
mA with a 1 Hz sample rate, and 10 mA with a 100 Hz scan rate. When the
CR1000KD Keyboard/Display is active, an additional 1 mA is added to the
current drain while enabling the backlight for the display adds 42 mA.
7.2.3 Power Sources
Related Topics:
• Power Input Terminals — Specifications
• Power Supplies — Quickstart
(p. 39)
• Power Supplies — Overview
(p. 86)