IM 12B06J07-02E-E
6
1 PREFACE
1.1 Introduction
The SC24V sensor with Variopin connector is
not a conventional pH sensor, but a differential
sensor that uses two dissimilar ion sensitive
glass membranes to generate the pH signal.
The measuring element is the same as a
conventional pH electrode, and the reference
similar to a Sodium ion electrode. Therefore the
SC24V can only be used in combination with
pH analyzers that feature:
• Dual high impedance sensor inputs
• Adjustable setting for the Isothermal Point
• Adjustable temperature coefficient
The SC24V differential measuring principle
has significant advantages over conventional
electrode designs in a variety of difficult
applications. The hermetically sealed reference
eliminates exposure of the reference fill solution
to the process, as there is no reference junction
to be affected by aging, plugging or poisoning
from the process. This greatly reduces
maintenance problems since the reference
stability of the differential sensor is then only
dependant on the sodium concentration of the
process.
The SC24V is ideally suited for difficult
applications where conventional electrodes
suffer from reference problems, especially
when high temperatures and high pressures
are involved. 70-80% of industrial users will fully
benefit from using the SC24V, as they will have
sufficient sodium levels in their processes for a
stable measurement. Examples of applications
where the sensor has proven to be successful
are Chlorine manufacturing by electrolysis of
brine and Bio-ethanol fermentation.
The only applications where the SC24V cannot
be used are those where the salt concentration
is fluctuating more than 30% or is too low, such
as in pure and ultrapure water processes.
1.2 Unpacking and Checking
Upon delivery, unpack the sensor carefully
and inspect it to ensure that it is not damaged
during shipment. If damage is found, retain the
original packing material and immediately notify
the carrier and the relevant local Yokogawa
Sales office. Make sure the Model Code and
Serial Number on the sensor are the same as
on the packing list.
1.3 Warranty and Service
Yokogawa products are guaranteed free from
defects in workmanship and materials under
normal use and service for a period of (typically)
12 months from the date of shipment from the
manufacturer. Individual sales organizations
can deviate from the typical warranty period,
and the conditions of sale relating to the
original purchase order should be consulted.
Damage caused by wear and tear, inadequate
maintenance, corrosion, or by the effects of
chemical processes is excluded from this
warranty coverage. In the event of a warranty
claim, the defective goods should be sent
(freight paid) to the Service Department of the
relevant Yokogawa Sales office for repair or
replacement (at Yokogawa’s discretion). The
following information must be included in the
letter accompanying the returned goods:
• Model Code and Serial Number.
• Original Purchase Order and Date.
• Length of time in service and description of
the process.
• Description of the fault and circumstances of
the failure.
• Process/environmental conditions that may
be related to the failure of the sensor.
• Statement as to whether warranty or non-
warranty service is requested.
IM12B06J07-02E-E_ed05.indd 6
14/01/16 09:46
