TSI Instruments DustTrak 8540, Operation And Service Manual

Page: 27 / 78

Setting Up 17
Click on the Flow tab to adjust the pump flow rate.
Figure 11: Checkout Application
– Flow tab
Click the green arrow to start the pump, allowing for a change to the
flow setpoint. The flow setpoint is factory set to 3 L/min total flow.
2 L/min of the total flow is measured aerosol flow. 1 L/min of total flow
is split off, filtered, and used for sheath flow. There is an internal

P
flowmeter in the DustTrak
™ instrument that controls flow rate to ±5%
of the factory setpoint. TSI
®
recommends checking the flows with an
external flow reference meter, especially when collecting data.
1.
Attach a flow calibrator (reference flowmeter) to inlet port. You
may use a bubble buret, mass flowmeter, dry piston or rotameter
as flow measurement devices.
2.
Click on the up or down arrows to achieve desired flow on the
reference flowmeter. Each click of the up or down arrow will
change the flow about 1%. Allow time between button presses to
let pump change to the new flow rate.
3.
Click Save once the desired flow rate is achieved. Select Undo to
return to the factory setpoint.
NOTE – Models 8540, 8540-M, 8542-M
The flow rate can be adjusted from approximately 1.5 to
4.0 L/min. If needed, this feature can be used to adjust the
flow rate to a value other than the factory setpoint, allowing
for the use with 3
rd
party size selective inlets (cyclones or
impactors) that may require a different flow rate.