Honeywell 4905 Style Conductivity Cells 70-82-25-18 - Manual (Page 12)

Installation
6 4905 Series Conductivity Cells – Installation and Maintenance 12/07
3.4 Flow-Type Mounting
The cross-channel or guard-tube hole in the cell must always be covered by the solution and the solution
level must be 1-1/2 inches above these holes. When mounting the cell in a pipe tee such as shown in
Figure 3-1, have the solution enter the tee from below and exit to the side. As shown, the guard-tube hole
is in line with the horizontal pipe run. However, if it is possible that the pipe line will not be full at all
times, locate the hole just below the exit pipe to insure flooding of the cell under all conditions. As shown
in Figure 3-1, always locate the cell on the pressure side, not the vacuum side of the pump. The flow-cell-
housing, an accessory part having 3/4” male inlet and female outlet threads, can be used for an in-line
measurement or in a bypass line as shown in Figure 3-1, depending upon the flow volume or pipe size.
Adapter bushings are available to convert inlet and outlet fittings to 1/4” female threads. See Section 0 .
The cell must be covered by the solution at all times. Therefore, make certain the lowest solution head is
higher than the cell location. See that an air bubble does not prevent the cell from filling properly.
Flow-cell housing can be used “in-line” only if a maximum flow of 2 gallons per minute can be tolerated.
To avoid cracking the 276127 flow-cell housing, use Teflon tape on cell threads and tighten cell only
enough to prevent leakage.
To install, tighten the cell into a 1” schedule 40 pipe tee. If the flow-cell housing is used, assemble the cell
and housing and install it in the process flow line or in a bypass line.
Preferred
Cell Locations
Cooler
Pump
Process
15"
(381mm)
a/n 23383
Figure 3-1 Typical Conductivity Measuring Installation
3.5 Immersion-Type Mounting for 04905 Series Cells
For use in applications where temperature does not exceed 85°C. The cell must be immersed to a level
above the cross-channel or guard tube hole and must be immersed to 1-1/2 inches above this hole if an
integral compensator is used. For most immersion applications, a 1/2” support pipe, preferably CPCV
must be threaded into the cell bushing, using Teflon tape to seal the threads, thus permitting adequate
immersion. Unless this pipe extension is used, do not immerse the top of the bushing. To insured that a
representative sample is measured at all times, the solution must circulate through the channels. In
quiescent solutions, provide sufficient agitation.
To install the cell, determine the length of 1/2” pipe required to give the immersion needed to keep the cell
completely immersed at all times. Up to six feet of pipe can be used for the standard cell having seven feet
of cable. Remove the small bushing at the top of the cell, slide it off the cable, and replace it with the 1/2-
inch pipe. At the top of the pipe slide a pipe coupling and the small bushing back over the leadwire as
shown in Fig. 3-1, or install a junction box to terminate the pipe.