Fema Electronica K40-LC, Руководство пользователя

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FEMA ELECTRÓNICA . SERIES K . K40-LC
14
1.12.8 Alarms
The instrument manages 3 independent internal alarms, each
one controlling the activation of an optional relay, transistor
or SSR control output. These outputs are optional
(see section
2)
and are installed at the free slots of the instrument
(see
section 1.18)
.
The instrument has three front leds that reflect the state of
the three internal alarms, identified as ‘1’, ‘2’ and ‘3’. For op -
tions with 4 and 6 relay outputs, see special modules R2, R4
and R6 at section 2.8 .
• Configurable parameters
Each alarm has several configuration parameters, starting
with the usual setpoint, hysteresis and maximum (alarm
active when reading is higher than setpoint) or minimum
(alarm active when reading is lower than minimum) alarm
types
(see Figure 6).
• Activation and deactivation delays
Each alarm can configure independent activation and deacti -
vation delays. These delays affect the alarm as a whole, and
the delay will affect the front led and the associated relay.
• Stability activation
The stability activation delays the alarm activation until the
reading is stable
(see Figure 7)
.
Application : the filling of a tank with liquid is controlled with
a load cell. Upon reaching 5000 liters, the alarm 1 activates to
stop the filling pump. After the pump has stopped, the liquid
is still moving inside the tank, and this movement is reflected
in weight and reading oscillations. Alarm 2 is configured as
‘stability alarm’ and activates when the liquid inside the tank
is at rest. At this moment, the tank can be removed safely.
• Second setpoint
Configuring a second setpoint creates ‘windowed alarms’.
The windowed alarm controls with a single relay output if
the reading is inside or outside the values defined
(see Fig-
ure 8)
.
• Inverted relay
Activate the ‘inverted relay’ function to invert the activation
logic of the associated relay.
• ‘ Locked alarms’
Activate the ‘locked alarms’ function to force the operator to
interact with the instrument when an alarm has activated.
Once activated, the alarm will remain locked at active state,
even if the reading returns to a value below setpoint, until
the operator manually unlocks the alarms by pressing the
front key ‘LE’ (
3
).
Reading
t
setpoint
hysteresis
Alarm as maximum, no
hysteresis and no delays
on
off
activation
delay
on
off
deactivation
delay
Alarm as maximum, with
hysteresis and delays
on
off
Alarm as minimum ,no
hysteresis and no delays
t
t
t
Figure 6 - Examples of alarms with 1 setpoint
Reading
t
Set points 1 and 2
Alarm 2 as maximum with
stability.
on
off
t
Alarm 1 as maximum.
on
off
t
AL1
AL2
5000
Figure 7 - Example of alarm with stability
Reading
t
Set point 2
Set point 1
Alarm as minimum, with
double setpoint, no hyster-
esis and no delays
on
off
t
Figure 8 - Example of alarm with double setpoint