ABB AW101

Water Hardness Analyzer
AW101 Testomat 4 Description of Displays and Operating Features
IM/AW101 Rev. C 7
4.4 Description of the Relay Outputs
LV1 and LV2 limit value outputs
To signal that a limit value has been exceeded, two volt-free
relay contacts are available. For both contacts the limit values,
hysteresis and alarm action can be programmed independently:
4.5 Diagnostic Alarm Messages
The Alarm output is a volt-free change-over relay contact.
During normal operation the contact between terminals 16/17 is
closed and the one between terminals 15/16 is open. If the
voltage fails or the alarm is activated, the contact between
terminals 15/16 is closed and the one between 16/17 is open.
The unit is equipped with a range of alarm notification functions.
 Activation:
The Alarm output remains activated (with terminals 15/16
closed) as long as the fault persists.
 Alarm Indicators:
Text and a red LED Alarm on the display indicate a fault.
 Alarm cancellation:
The Alarm output condition is cancelled using the Horn
key.
An error message can only be deleted after the fault has
been corrected.
Exception – reagent low level, this message is confirmed
in the M-menu by entering in the new reagent level.
The following conditions activate the Alarm output and are
displayed:
 Low-water pressure
 Low reagent level
 Function fault optics
 Measuring fault – dirty chamber
 Measuring fault – analysis
 Measuring fault – turbid sample
 Function fault – dosing pump
 Measuring range exceeded
 Function fault outlet to drain
Error messages are described in Table 6.1, page 14.
For a more detailed description of the programming refer to
page 11. For general maintenance refer to page 15.
Function Type of
contact
Action
LV1
active when in
excess of limit
value 1
Volt-free
change-over
contact
Programmable:
 Continuous contact
 Impulse (1 … 99
seconds/minutes)
 Interval (1 … 99
seconds/minutes)
 Two-step regulator
 Hysteresis (1, 2 or 3 limit
value in excess)
LV2
active when in
excess of limit
value 2
Volt-free
change-over
contact
Programmable:
 Continuous contact
 Impulse (1 … 99
seconds/minutes)
 Interval (1 … 99
seconds/minutes)
 Hysteresis (1, 2 or 3 limit
value in excess)
Table 4.1 Relay Outputs