GT-521S Manual Rev D
Page 14
5.2.1. Location Number
The location number is used to assign a unique number to a location or area. This
important field is included in sample data records (display, printer and serial output).
5.2.2. Sample Time
The sample time determines the amount of time that counts are accumulated while the
pump is running. The length of the sample is user settable from 1
– 9999 seconds.
5.2.3. Hold Time
The Hold time is the time between samples when sampling more than a single sample.
The Hold time is user settable from 0
– 9999 seconds. The pump will remain on during
the hold period if the Hold time is 60 seconds or less. If the Hold time is greater than 60
seconds, the pump will stop after each sample, and start a few seconds before the next
sample. Hold times greater than 60 seconds will increase pump life.
5.2.4. Samples
The samples setting controls the number of samples to take as illustrated below.
Selection
Description
REPEAT
Repeat configures the unit for continuous sampling.
SINGLE
Single configures the unit for a single sample.
002-999
Configures the unit to take N samples.
5.3.
Settings Screen
Figure 12 shows the Settings Screen. The four parameters are covered in the sections
immediately following.
VOLUME: CF
TEMP: C
COUNT NORMAL
Figure 12
– Settings Screen
5.3.1. Volume
The GT-521S supports total counts (TC), particles per liter (/L), particles per cubic foot
(CF), and particles per cubic meter (M3). Particle count information updates while the
unit is sampling. Concentration values (/L, CF, M3) are time dependent so these values
may fluctuate early in the sample; however, after several seconds the measurement will
stabilize. Longer samples (e.g. 60 seconds) will improve concentration measurement
accuracy. In total count mode, counts accumulate throughout the sample time.
