User manual

User Guide
6.4 CR1000 Datalogger
The CR1000 datalogger supports changing the address in a similar way to the
CR200. In terminal mode issue the SDI12 command, then give the control port
number in response to the prompt. The normal SDI12 command can then be
entered (there is no need to enter the “SDI12” prefix as with the CR200). If
changing the address you will initially get a “fail” message (as with the CR200).
To terminate the SDI12 terminal mode press <enter> with no command.
7. Maintenance and Calibration
The CS215 probe requires minimal maintenance.
• Check monthly to make sure that the radiation shield is free from dust and
debris.
• Clear the white filter on the end of the sensor of similar debris. If dirt or salt
is engrained into the filter it should be cleaned with clean water or more
simply replaced. Make sure the filter is done up firmly with your fingers – do
not over tighten.
The life of the humidity chip element is quoted as many years with a typical drift
of less than 1% per year when used in ‘clean’ environments. However, as it can be
difficult to define what the sensor has been exposed to and as the element of the
CS215 is relatively low cost we recommend that you replace the sensor element at
the normal interval you would recalibrate similar probes, e.g. annually. Replacing
the element effectively brings the probe back to a factory calibration state both for
temperature and RH without incurring a costly return for factory calibration.
If you wish to have an old element’s calibration checked so that you can formally
record the probe’s pre-calibration state (pre-sensor replacement), you can measure
its performance by plugging it into another sensor. For a fee, Campbell Scientific
can provide a certificate of performance for sensor elements returned to them.
7.1 Sensor Element Replacement
To replace the element:
1. Disconnect the sensor from the 12 V power supply.
2. Remove the filter by unscrewing it in an anti-clockwise direction when
looking towards the tip of the sensor.
CAUTION: The filter cap unscrews from the probe.
Attempting to pull if off will destroy it.
3. Identify the sensor element referring to figure 4a below, which shows a side-
on view of the end of the probe and sensor element. Before removing the
element carefully study the probe and note its orientation after reading the
following description:
• The element plugs into the black plastic socket that protrudes by about
1mm from the end of the metal body of the sensor.
• There are eight holes in the socket, whilst the element only has four pins
in line.
• The element will work when fitted into either side of socket but must be
installed in one of the two possible orientations to work.
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