Thermo Scientific DCT6088, User Manual

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Primary Displays & Menus
The Flow Menu
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Low Flow Cutoff setup menu (34)
When a zero flow condition occurs (for example, as the result of a
pump being shut off), internal sloshing, check valve leakage, and other
fluid movement can prevent the flowmeter from reading total zero.
This phenomenon can result in totalizer errors. Minimize these errors
by entering a low flow cutoff, which drives the flowmeter to zero for
flow rates at or below the specified value. If the flow rate falls below the
low flow cutoff value, the indicated flow rate is driven to zero and the
totalizers stop incrementing. This is the case regardless of flow
direction.
Figure 5–16. Low Flow Cutoff setup menu
For example, if you enter a low flow cutoff of 0.1 ft/s (0.03 m/s), the
flowmeter will be driven to zero for flow rates less than 0.1 ft/s in the
positive direction and greater than -0.1 ft/s in the negative direction.
Figure 5–17.
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Low Signal Cutoff setup menu (35)
Empty pipes or solids, bubbles, or voids in the flow stream may cause
temporary drops in signal strength and erroneous readings. Minimize
the effect of these dropouts by setting a low signal cutoff, which drives
the flowmeter to the loss-of-signal (LOS)condition. The low signal
cutoff should be set at the minimum acceptable signal amplitude.
To set the low signal cutoff, access the Low Signal Cutoff setup menu
(35). Enter the low signal cutoff and press
ENTER .
Figure 5–18. Low Signal Cutoff setup menu
5-6 DCT6088 User Guide Thermo Fisher Scientific