Hach AF7000 SCM Manual Básico Del Usuario página 14

Figure 4 Display and keypad overview
1 Top display
2 Bottom display
3 DOWN arrow key
Item Name
(1) Top display
(2) Bottom display
(3) DOWN arrow key Select a menu or option, set or change a value
(4) UP arrow key
(5) Enter key
14 English
4 UP arrow key
5 Enter key
6 Menu/Cancel key
Table 3 Display and keypad descriptions
Description
Raw streaming current value (the same value shown in the bottom display) until the
zero point has been set. When the zero point is set, the display shows the deviation
from the raw streaming current value.
• 0 = Optimal amount of coagulant if the user has set the zero point based on the zeta
potential or the jar test
• – XX = The streaming current value is less than the optimum value. Coagulant may
need to be added if the user has set the zero point based on the zeta potential or
the jar test.
• + XX = The streaming current value is more than the optimum value. The coagulant
feed may need to be stopped or reduced if the user has set the zero point based on
the zeta potential or the jar test.
Raw streaming current value
Note: "PXX"(e.g., P66) shows when the instrument has a PID controller that is set to manual mode.
Push Auto/Manual to show the raw streaming current value.
"PXX" identifies the percentage at which the PID controller is operating. For example, if the
instrument output signal (4–20 mA) is 4 mA, "P00" shows. If the instrument output signal is 12 mA,
"P50" shows. The percentage shown depends on the user settings.
To adjust the zero point, push and hold an arrow key for 2 seconds, then push the
applicable arrow key.
• DOWN arrow = increase the zero point
• UP arrow = decrease the zero point
Note: When the optional 4–20 mA PID controller card is installed, the controller must be in manual
mode to adjust the zero point. Push Auto/Manual to go to manual mode.
Select a menu item or accept an entry
7 Set Zero key
8 Auto/Manual key