Titan Metraflow 240-020, Инструкция по эксплуатации

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©Titan Enterprises Ltd 2018 www.flowmeters.co.uk MetraflowManual_v1219
The Latching box gives the user three options of None, High Threshold
and Low Threshold.

“None” will cause the alarm to be triggered when the threshold flow
is met. The alarm state will then reset in accordance with the user
set Hysteresis*.

“High Threshold” will cause an alarm signal to Latch on when flow
is seen above the set value.

“Low Threshold” will cause an alarm signal to Latch on when flow is
seen below the set value.
* Hysteresis (%): This is used when Latching is set to NONE to prevent “fluttering” of the alarm signal
when flow is around the threshold level.
LATCHED alarms will remain active and the local display will show “LATCH” until they are reset. RESET
LATCH ALARMS by either a signal input on one of the other Input/Output PINS, or by pressing and
holding the left hand button on the local display on the flow meter for 3 seconds.
Note the alarm points are driven by the display value on the “flow reading” screen. Any changes to the
filter value of the display will affect the response time of the alarm points so there are two adjustable
parameters to ensure “fluttering” does not happen with small flow fluctuations - response time and
hysteresis.
INVERT – This check box allows the user to invert the operation of the signal.
Invert:

Checked – Alarm output logic HIGH.
For details see the Alarm logic table or hover mouse over the set point to see the action of the output
with the chosen settings.
Dual flow alarm: Checking this will enable a range of flow to be entered.
When the flow is outside/inside of this range the alarm will be triggered.
The remaining settings in the input box are the same as for single flow
alarms.
 When no Latching is chosen the alarm will automatically reset in proportion to the user
set Hysteresis.

The Latched Alarm can be reset by a signal input on one of the other Input/Output
PINS, or by pressing and holding the left hand button on the local display on the flow
meter for 3 seconds.