Hach 54400-18, Instrument Manual

Page: 41 / 74

Section 2
Page 39
54400_start.fm
Instrument Menu Structure
Alternatively, the output can be bracketed between 2–4 mg/L to control
chemical feeds, or the signal can be inverted by assigning a higher mg/L
reading for REC LO and a lower mg/L reading to REC HI.
Initially, select an output span that will cover the expected range of chlorine
concentration in the sample. Determine the correct minimum and maximum
values by monitoring chlorine values in your sample over time. Adjust the
minimum and maximum values if necessary, to obtain the best span for your
specific application.
Adjust the recorder output minimum and maximum values using the analyzer
keypad as follows:
1. Press the
MENU
key.
2. Use the
DOWN ARROW
key to scroll to
RECR DR
menu and press
ENTER
.
The display will show
REC LO
and a mg/L reading. Press the
DOWN
ARROW
key again to move to
REC HI
or
ON SYSTEM ALARM
.
3. Press
ENTER
to change the displayed mg/L reading for
REC LO
or
REC HI
. The digit to be changed will flash.
4. Press the
ARROW
keys to change the digit or move to another digit.
Appropriate values and selections are shown below. When the value is
correct, press
ENTER
to accept.
• REC LO —0.0 mg/L to 5.0 mg/L limits.
• REC HI — 0.0 mg/L to 5.0 mg/L limits.
• ON SYSTEM ALARM —Select minimum, maximum, or hold to define
the recorder output when a system alarm is initiated.
5. Press
EXIT
to return to the main menu. Press
EXIT
again to return to
normal operation.
2.7.3.1 Changing to 0 to 20 mA Output Range
Set the lower end of the output range to 0 mA instead of 4 mA as follows:
1. Press the
MENU
key then use the
UP ARROW
key to scroll to the
SETUP
menu. Press
ENTER
.
2. Use the
DOWN ARROW
key to scroll to
REC ADJUST
and press
ENTER.
Note: A large number may be displayed for the minimum value, this number refers to
counts, not milliamps. Proceed with step 4.
3. Use the
ARROW
keys to adjust the displayed value to 0. Press
ENTER
to
accept the value.
4. Press
EXIT
twice to return to normal operation.
2.7.4 Maintenance Menus
The following selections allow the user to perform standard maintenance
tasks. Use the
ARROW
keys to scroll through the menu selections, then press
ENTER
to select the displayed menu option.