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Installation
4.9.1 AC power installation
Warning
Electric shock hazard. The temperature of the power supply will increase when the
sampler pump is operating. If the time interval between sample cycles is too short,
the power supply can become overheated resulting in power supply failure or loss
of power supply safe guards.
In heavy industrial environments it is good practice to use a power line filter or to connect
the controller to a quiet electrical branch circuit.
To prevent overheating the power supply when it is used with a sampler, complete these
steps:
1.
Determine the amount of time that the pump will run continuously during a sample
cycle. Include all stages: pre-purge, intake rinse, sample, sample retries and
post-purge.
Note: The programmed options for each sample cycle, in addition to the purge states, affect the
amount of time that the pump is on continuously.
2.
Use the graph to estimate the amount of time that the pump must be off in between
sample cycles. Refer to
3.
Make sure the pacing or time interval in the sampler program allows enough time for
the pump to be off between sample cycles.
Note: When the ambient temperature is 50 ºC (122 ºF), do not allow the pump to run continuously
for more than 10 minutes.
Examples
1.
Assume that the pump is on continuously for 10 minutes for a given sample cycle. On
the graph, find 10 minutes on the bottom (horizontal) axis. Draw a vertical line up
from the 10 minute mark until it intersects the 50 ºC (122 ºF) line. From the
intersection, draw a horizontal line to the left to the vertical axis. The point where the
horizontal line intersects the vertical axis, in this case 30 minutes, is the time in
minutes that the pump must stay off before the next sample cycle begins.
2.
Assume that the pump is on continuously for 2 minutes. The pump must stay off for at
least 6 minutes before the next sample cycle begins.
Goodnal STP ST041 Pre Treatment (Sigma 900 MAX All Weather Refrigerated Sampler) Vendor Manual
Q-Pulse Id VM373
Active 29/10/2013
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