Azbil Micro Flow MQV0002, Руководство пользователя

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5-14
Chapter 5. ADVANCED OPERATION
SP
PV
ON(ALM)
OFF
a
.
h
.
hy a
.
L
.
hy
a
.
hi a
.
lO
*3. Only items corresponding to the alarm type selected in flow rate alarm setup (
c- 15
in the function setup) can be set.
*4. These alarms can be set when (1 to 3) is set for flow rate alarm setup type (
c- 15
) and valve amperage alarm setup type
(
c-20
) in the function setup.
*5. This cannot be set when "0: Not used (OFF all times)" has been selected for
c-07
and
c-08
event output type
assignment in the function setup.
*6. This can be set only when "0: Conversion factor for each gas type set by the user" has been selected for the
c- 18
or
c-26
gas type selection 1 or 2 in the function setup.
*7. This can be set only if a suitable alarm type is selected in the
c-20
valve amperage alarm setup (in the function setup).
*8. This can be set only when "8 to 10: PV upper / lower limit event 1, 2" has been selected for the
c-07
and
c-08
event
output type assignment in the function setup.
*9. This can be set only when "1 and 2: SP ramp control" has been selected for the
c-27
SP ramp control function in the
function setup.
*10. This can be set only when "1: Function enabled" has been selected for the
c-28
analog optional scaling function in the
function setup.
*11. This can be set only when "1: Cumulative flow event" has been selected as event output type in
c-07
or
c-08
in
the function setup or when "1: Function enabled" has been selected for the automatic valve shut-off function upon
occurrence of the cumulative flow event (
c- 13
) .
*12. This can be set only when "1: Function enabled" has been selected for the
c-29
forced PV zero function in the function
setup.
*13. This can be set only if suitable limit type is selected for the
c-35
SP limit function in the function setup.
*14. When the full scale flow rate is changed by changing function setup
C- 18
or
C-26
(gas type setup) or
C-24
or
C-25
(control flow rate range setting), the parameter setup must also be changed. In this case, the setting range can be
obtained by multiplying the modified full scale flow rate by the ratio enclosed in brackets.
Handling Precautions
•
The valve amperage changes greatly according to the differential pressure
even if the flow rate is the same. For this reason, the valve amperage alarm
function cannot be used under unstable differential pressure conditions.
•
Even under stable differential pressure conditions, hysteresis characteristics
(electric current to the valve differs even if the flow rate is the same) are
applied to the relationship between the valve amperage and the flow rate.
So, to use the valve amperage alarm function, first sufficiently test under
operating conditions to check the valve amperage range, and then determine
the alarm amperage setting.