Ele 521-050, Operating Instructions Manual

Page: 9 / 16

Dissolved Oxygen Meter
521-050
9 9907X0046 Issue 1
10.2 Recalling data
Pressing the RCL key recalls the last stored reading onto the display.
The instrument is now in RCL mode, indicated by the RCL annunciator
at the top of the display.
The
▲▼ keys are used to select previously stored data. The storage
location is indicated by rCL and a number (1-32) momentarily
displayed prior to the data.
To clear all readings press and hold the CAL key (>3 seconds) while in
RCL mode. When all stored readings are cleared the display will
momentarily show
CLr ALL . The instrument will then return to the
main operating mode.
If storage locations are empty and the RCL key is pressed, the display will
show
ALL CLr .
NOTE: It is not possible to delete individual stored readings.
11 Good Practice Guidelines
a. Ensure the membrane is kept wet at all times. When not in use
the probe should be stored with the tip in a beaker of deionised
water. For longer periods (overnight) the protective sheath
should be fitted, with the sponge insert soaked in distilled
water. This will prevent the electrolyte fill solution from drying
out due to loss of water through the porous membrane.
b. Ensure the probe is polarised prior to use. It is essential to perform
this procedure after replacement of the membrane or probe. A 30
minute period of polarisation is required.
c. When replacing the membrane ensure no air bubbles are trapped in
the electrolyte fill solution and that the membrane is not creased or
damaged after fitting. If the probe response is sluggish, or the readout
is unstable after membrane replacement, clean the anode and
cathode (refer to Maintenance in Section 12).
d. The probe is fitted with a temperature compensating element. This is
housed underneath the silver ring on the probe body. Always ensure
the probe is immersed in solution to a depth suitable to cover this
ring. Allow sufficient time for these to respond if measuring samples
with varying temperatures or where sample temperature is
significantly different to ambient temperature.