Casella CEL Vortex personal sampling pumps - Manual (Page 10)

3. SAMPLING
The battery must be fully charged to ensure an 8 hour run, especially for
filters producing a high initial pressure drop.
The sampler is designed to work at maximum efficiency for flow rates
between 0.5 and 3.5 litres/min. The flow rate is accurately controlled to
within 5% for pressure drop variations appropriate to the selected flow rate.
The pressure drop limits are also related to the selected flow rate:
Typically 15 cm H
2
O max. at 3.5 litres/min, and 40 cm H
2
O at
2 litres/ minute.
The sampler is suited to the vast majority of commonly used sampling
methods and filter media.
Note: The sampler should never be run without a filter on the inlet.
3.1 Check List Before Sampling
1. Make sure the battery has been fully charged.
2. Ensure that the sampling head is correctly fitted with no leaks.
3. If the flow rate cannot be obtained with similar conditions to previous
occasions, a leakage may be present.
Sampling
Page 10 of 16
VORTEX Standard 2 & VORTEX Timer 2
PERSONAL SAMPLING PUMPS Handbook