Instruction Manual

6X Series Liquid-Cooled Transmitter Chapter 5, Maintenance
Instruction Manual, Rev. 0 5-2
Figure 5-2: Input and Output Valves
Let the water run for approximately 3 seconds. This should clean the strainer. Repeat
for the strainer in the other line. Periodically, the strainers should be removed and
cleaned. This is accomplished by first isolating the desired pump and strainer by turning
off the input and output valves to the pump. See Figure 5-2. Place a bucket under the
drain and open the drain valve. Remove the 1.5” nut from the bottom of the strainer
assembly and remove the strainer, noting the orientation of the strainer. Clean the
strainer, may need to use a metal brush, and return it to the strainer assembly in the
same position as removed. Tighten the 1.5” nut. Repeat for the strainer in the other
line. Turn on the input and output valves to the pump. Also, check and clean the single
strainer located in the input line to the reservoir tank in the same manner as described
for the output strainers.
If you are doing the initial installation flushing, connect the water lines to the 6X and the
Test Load.
5.1.2.2: Checking the glycol concentration level and PH value
It is recommended to use Dow Chemicals’ Dowtherm SR-1 at a 50/50 mix with distilled
water for cooling the 6X transmitter.
The concentration and condition of the mixture should be checked monthly. This can be
done with a hydrometer, if the temperature of the mixture is known. However, a
refractometer will indicate the concentration regardless of the temperature of the
mixture. To test the coolant mixture for pH and concentration, Axcera recommends the
use of a pH-meter supplied by Misco and a refractometer supplied by Misco (7084 VP+
[
o
F] or 7064 VP+ [
o
C]). The pH value of the mixture is important. The glycol mixture
must be monitored at monthly intervals for the pH value. The desired range of the
value is between 8 and 10. If this value falls below 8 and is ignored, the mixture will
rapidly become acidic and could damage the 6X amplifier trays. When the pH value of
the mixture falls below 8, the entire mixture must be replaced or a small, 50% diluted
quantity of sodium hydroxide (very caustic) or potassium hydroxide (less caustic) should
be added to the system. This will bring the pH back into the required range. The use of
sodium hydroxide or potassium hydroxide can only be repeated three times, after which
the whole mixture should be replaced.
If, when the coolant is inspected, the color of the glycol mixture has changed to gray or
black, or there is an oily layer, a burnt odor, or any sludge in the mixture, this will
indicate a need for the replacement of the entire mixture.
Output
Valves
Input
Valves