Fill, Menu – American Magnetics 286 Multi-Sensor Liquid Level Instrument (CE-Marked) User Manual

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Operation

Menu Reference

A changeover time of zero is not allowed, since not specifying a
timeout would fill from only one storage vessel indefinitely. The
default setting is 10 minutes.

4.3.8.5

Fill Timeout

If the contacts method of empty detection is selected, a fill timeout
is still available as a failsafe backup to the contacts indication. If a
fill timeout greater than zero is specified, then if an auto-fill cycle
does not complete within the specified time, the Model 286 ignores
the remote contact indication and de-energizes the respective AC
output. After the fill timeout expires, a manual cycle of the AC
output state is required in order to reset the auto-fill logic for the
respective AC output, or the instrument power must be cycled.

If a zero fill timeout is specified, as long as the remote contact is
closed, the Model 286 will attempt to fill from the respective storage
vessel indefinitely. A value of zero minutes is the default setting.

Note

In order to reset the fill timer for a given AC output after expiration,
the fill mode for that AC output must be set to either ON or OFF via
the keypad or remote interface, or the power to the instrument must
be cycled..

4.3.9

FILL Menu in Pre-Cool Mode

In the pre-cool controller mode, the FILL menu, accessible by pressing the

FILL

key with Channel 1 selected, provides four menu screens. Once in the

FILL menu, the screens are accessible by repeatedly pressing the

key, and include interfaces for setting the AC output states, selecting the
empty detection method, and setting timeouts. The pre-cool mode manages
an auto-fill cycle

for one controlled dewar using AC Output 1. AC Output

2 is used to control a vent valve for purposes of pre-cooling a transfer line
from a storage vessel.

1. An “auto-fill cycle” in the pre-cool mode is initiated by a liquid level less than the B

setpoint of Channel 1, and is terminated once the liquid level reaches or exceeds
the A setpoint of Channel 1. The first phase of the auto-fill cycle is the user-defined
pre-cool time using the vent valve. The pre-cool time is repeated at the beginning of
each auto-fill cycle.

Fill Timeout:

0.0 min