User manual

12
81505_MHW_450_03-2013_ENG
• Prot
6 • ALARM
time
AL + Hyst1
AL
alarm
(*)
For AL = reverse absolute alarm (low) with positive Hyst1, AL1 t = 1
(*) = OFF if disabled on power-up
For AL = symmetrical Lo absolute alarm with Hyst1, AL1 t = 5
For AL = symmetrical Hi absolute alarm with Hyst1, AL1 t = 4
* Minimum hysteresis = 2 scale points
Normal absolute alarm Symmetrical absolute alarm
reverse
direct
AL
AL + [ Hyst1* ]
AL - [ Hyst1* ]
time
For AL = Lo deviation alarm with negative Hyst 1, AL1 t = 3
For AL = Hi deviation alarm with negative Hyst 1, AL1 t = 2
For AL = Symmetrical Lo deviation alarm with Hyst 1, AL1 t = 7
For AL = Symmetrical Hi deviation alarm with Hyst 1, AL1 t = 6
time
SP+AL
SP
reverse
direct
SP+AL
SP
reverse
direct
time
Hyst1
Symmetrical deviation Alarm Symmetrical deviation Alarm
SP-AL
Proportional Action:
action in which contribution to output is proportional to deviation at input (deviation = difference between controlled variable and
setpoint).
Derivative Action:
action in which contribution to output is proportional to rate of variation input deviation.
Integral Action:
action in which contribution to output is proportional to integral of time of input deviation.
Influence of Proportional, Derivative and Integral actions on response of process under control
* An increase in P.B. reduces oscillations but increases deviation.
* A reduction in P.B. reduces the deviation but provokes oscillations of the controlled variable (the system tends to be unstable
if P.B. value is too low).
* An increase in Derivative Action corresponds to an increase in Derivative Time, reduces deviation and prevents oscillation up
to a critical value of Derivative Time, beyond which deviation increases and prolonged oscillations occur.
* An increase in Integral Action corresponds to a reduction in Integral Time, and tends to eliminate deviation between the
controlled variable and the setpoint when the system is running at rated speed.
If the Integral Time value is too long (Weak integral action), deviation between the controlled variable and the setpoint may
persist.
Contact GEFRAN for more information on control actions.
7 • CONTROL ACTIONS
Pro
Protection code
Pro Display Change
0 SP, alarm, OutP SP, alarm
1 SP, alarm, OutP SP
2 SP SP
3 SP
+4 disables InP, Out
+8 disables CFG
+16 disables “SW turn on - turn off”
+32 disables MAN/AUTO key
+ 64 to disable manual power memorization
To activate the turn off SW function, press keys F
F +
Δ for 5 secs. in P.V.
To return to normal functioning, press key F for
5 secs.
Configuraz.
64
Default Custom