Hanna Instruments HI 7635 User manual

Instruction Manual
HI 7635 - HI 7636
4-PIN IN-LINE
CONDUCTIVITY PROBES
Dear Customer,
Thank you for choosing a Hanna product.
This manual will provide you with the necessary information
for the correct use of the probe. Please read it carefully
before installing the probe.
If you need additional technical information, do not hesitate
to e-mail us at [email protected].
Hanna Instruments reserves the right to modify the design, construction and
appearance of its products without advance notice.
GENERAL DESCRIPTION
HI 7635 and HI 7636 are one-piece-molded conductivity
probes with pipe threads (1" NPT) at both ends.
This allows the probes to attach to an in-line system, and to
be used in conjunction with the HI 8936 conductivity
transmitters.
Measurements are highly accurate, and performed by using
a 4-ring potentiometric measuring method.
Probes require very little maintenance; the construction of
the housing is rugged, fiber-reinforced polypropylene.
HI 7635 also incorporates a built-in NTC sensor for tempera-
ture compensated conductivity measurements.
The max working pressure of these units is 5 bar (72.5 psi).
Do not use in systems where the temperature exceeds
80°C (176°F).
TYPICAL IN-LINE ASSEMBLY FOR HI 7635 (or HI 7636).
INSTALLATION
For the installation of the in-line conductivity probes, it is
necessary to use rubber seals between the probe and the
pipe or elbow joints. A pipe sealant is also recommended to
ensure a leak free joint. When screwing the joints, take care
not to overtighten as excessive pressures can cause the probe
damage.
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The probes are supplied with a 4 m cable. The wires from
the cable must be connected to the HI 8936 process
Conductivity Transmitter as shown below. The connections
are color coded for an easy installation.
CONNECTIONS
BLACK NTC SENSOR (HI 7635 only)
RED NTC SENSOR (HI 7635 only)
GREY/BROWN probe pin 1
BLUE probe pin 2
WHITE probe pin 3
GREEN probe pin 4
TYPICAL CONNECTION OF THE HI 7635 (or HI 7636) PROBE
AND THE HI 8936 TRANSMITTER TO THE HI 8931 CON-
TROLLER.
MECHANICAL DIMENSIONS
73mm
2.87"
52mm
2.04"
1" NPT
142mm
5.60"
The probes can be compensated for normal contamination
by a process of re-calibration. However, it is recommended to
remove regularly the process conductivity probes from the
system for maintenance.
Deposits on the probe can be removed by immersing it in
0.1N Hydrochloric acid for about 30 minutes. Heavier
deposits may demand longer immersion time.
Clean the electrode thoroughly with water prior to the
reinstallation. On reinstalling, check the seals carefully to
ensure a leak connection.
Note: Always recalibrate the meter when attaching a new
probe.
PROBE MAINTENANCE WARRANTY
All Hanna Instruments probes are warranted for a period of six months.
This warranty is limited to repair or replacement free of charge.
Damage due to accidents, misuse, tampering or lack of prescribed main-
tenance are not covered.
If service is required, contact the dealer from whom you purchased the
instrument. If under warranty, report the model number, date of pur-
chase, serial number and the nature of the problem. If the repair is not
covered by the warranty, you will be notified of the charges incurred. If
the instrument is to be returned to Hanna Instruments, first obtain a
Returned Goods Authorization Number from the Customer Service depart-
ment and then send it with shipment costs prepaid. If the repair is not
covered by the warranty, you will be notified of the charge for repair or
replacement. When shipping any instrument, make sure it is properly
packaged for complete protection.
All rights are reserved. Reproduction in whole or in part is prohibited without the written
consent of the copyright owner.
IST7635R1 06/05