Teledyne 4250 Installation And Operation Manual page 129

Figure 4-8 pH Parameter Module
The mounting rings are held in place by the outward force of
spring pressure in the smaller sizes and by a screw arrangement
in the larger sizes. After mounting the probe in the ring or strap,
route the cable out of the stream so it will not trap debris that
could clog the sewer.
Mount the pH Module within 25 feet of the probe, but in a
location higher than the highest anticipated level for the flow
stream. The amplifier box is sealed and will withstand tem-
porary submersion, but this should be avoided.
Note
Do not connect an Isco pH probe and temperature probe to the
201 module at the same time. The "Temperature Probe" input
on the 201 module is for use ONLY with non-Isco pH probes
that do not have built-in temperature sensing. The Isco pH
probe contains its own integral temperature sensor, which, if
connected in parallel with a separate temperature probe, will
cause erroneous readings.
Note
When installing the pH probe and its sensor carrier, make sure
the mounting slots on the carrier are completely pressed into
the mating tabs on the ring. The probe relies on a full engage-
ment between tabs and slots for secure mounting. If the slots
are loose against the tabs, the probe may be swept away by
the force of the stream.
Always mount the probe in an easily-accessible location, because
you will need to clean it from time to time. Also, all pH probes are
consumable items, meaning that they will eventually fail and
have to be replaced. The probe is due for replacement when you
4250 Flow Meter
Section 4 Options and Accessories
4-19