Hach Sigma 1600, Instrument Manual

Page: 19 / 50

Section 2
Page 19
6507installation.fm
Pump Control Timer Option
Figure 7 Series Loop Wiring
2.6 Pump Control Timer Option
The pump control timer option (Cat. No. 1662) allows the pump that supplies
the wastewater to the sampler to be turned off during the Interval Between
Samples. A sampler equipped with this option will have two potentiometers
with screwdriver adjustments located between the 1 amp fuse holder and the
power
ON
button on the control panel.
The potentiometer located near the 1 amp fuse holder controls the Pump On
time from 2–90 seconds. To set the pump control timer:
• Turn the screwdriver adjustment clockwise to increase the pump running
time or;
• Turn the screwdriver adjustment counterclockwise to decrease the pump
running time.
Set the adjustment so the pump will run for a sufficient time to ensure
complete purging of the inlet piping to the sampler and the sample chamber.
To ensure flow through the sampler chamber at the instant a sample is taken,
slightly adjust the time longer than the Sample Delay.
Note: Set the “Sample Delay”
adjustment for a sufficient time so
the sample intake line and chamber
are flushed with the new sample
liquid before the sample is taken.
The potentiometer located near the power
ON
button controls the time for the
Sample Delay from 2–90 seconds. To set the Sample Delay:
• Turn the screwdriver adjustment clockwise to increase the sample
delay time or;
• Turn the screwdriver adjustment counterclockwise to decrease the
sample delay time.