Form 37182 Rev 201019
Page 7 of 12
Using a CPC and Dual, Tri, or Quad Adjustable Low Flow Tube Holder (Figure 3)
Set/Calibrate Flow Rate for Multiple Tubes
Do not operate pump in hazardous or explosive locations. Pump is designed for applications that do not require intrinsic safety
.
• Requires Constant Pressure Controller (CPC) and Adjustable Low Flow Tube Holder (see Accessories). The low flow tube holder used with CPC
allows up to four tube samples to be taken simultaneously, each at different flow rates if desired.
• Allow pump to equilibrate after moving it from one temperature extreme to another.
• Calibrate/verify pump flow rate before and after each sampling operation using the tube holder and pump to be used for sampling.
• Set the flow rate through the pump first and then calibrate the flow rate through each sorbent tube.
Pump Flow Rate
Follow these important steps before proceeding.
1. Ensure that the battery is fully charged and that the pump has run for 5 minutes before calibrating. Leave pump running.
2. Prepare a calibrator
(see calibrator instructions)
. Using flexible tubing, connect the calibrator outlet (suction port) to the pump inlet.
3. Calculate the sum of all tube flow rates. The maximum flow rate through any one tube is 500 ml/min.*
a. If the sum is ≤ 1000 ml/min, set the pump flow rate to 1.5 L/min.
b. If the sum is > 1000 ml/min, multiply that number by 0.15 and total the two numbers. Set the pump flow rate for the resulting
new sum. (
Example:
Sampling with three sorbent tubes, each with a flow rate of 500 ml/min.* The sum of the tube flow rates is
calculated as 3 x 500 = 1500. Determining a 15% higher flow rate is calculated as 1500 x 0.15 = 225. Calculating the final pump
flow setting would be 1500 + 225 = 1725 ml/min.)
* Back pressure across some sample tubes can be higher than average. In these instances, the maximum flow rate of 500 ml/min per tube may not
be achieved.
4. Using a small screwdriver, turn the flow adjustment screw on top of the pump
(Figure 1)
,
clockwise
to increase or
counterclockwise
to decrease flow, until the calibrator indicates the required flow rate.
5. Remove tubing from the pump inlet and calibrator outlet.
Flow Rate Through Sorbent Tubes
1. Attach the tubing on the CPC outlet (side of the CPC without a label) to the pump inlet. Attach the Adjustable Low Flow Holder to
the CPC inlet (marked “To Sample”).
See Figure 4.
2. Break tips off the representative sorbent tubes and insert them into the rubber sleeves on the holder
(arrow on each tube pointing
toward pump)
. Place unopened tubes in any unused ports to “seal” them.
3. Label all representative sorbent tubes and ports.
4. Using flexible tubing, connect the exposed end of the first representative tube to the calibrator outlet (suction port).
Figure 3.
Quad Adjustable Low Flow Tube Holder
Top view of flow
adjust screws
Anti-tamper cover
Low flow holder outlet
Sorbent sample tube
Rubber sleeve
Clothing clip
Flow adjust screws
Protective cover
