Toshiba LF434 - Manual (Page 109)

TOSHIBA
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10. Digital I/O Functions
i hc Ll^’404 converter hu^onc stimdard digital output (DOl) terminal. This terminal can be
used in various ways, such as a pulse output, or an alarm output terminal. One more digital
output (D02) and one digital input (Dl) arc optionally available.
Digital 1,^0 functions described below can be assigned for DOl, DQ2 and Di.
Functions Description
f’otali/ation ■ The converter loiali^es volumetric flow values.
■ The totalized flow can be output as a pulse signal (DOi only)
scaled by a user-specified factor (counting rate)*
■ The totalizer and pulse signal (DOl only) can be controlled
(starts, stops and resets) with an external signal (DI),
Multiple Ranges
■ Multiple measuring ranges can be switched Eiccording to the
process flow rales cither automatically or by an external
signal (DI).
Forward and Reverse
flow measurements
■ I’orw'ard and reverse flows can be measured. The forward
and reverse flow measurements can be used together with
multiple range switching function.
1 ligh and Low Limit
Alarms
■ Outputs an alarm signal (DOl or D02) when the procctis
signal exceeds or inlays below the limit values.
Empty Ripe Alarm
■ The detector pipe musi be filled w'ith fluid all the time.
When it is not filled with fluid, the converter outputs an
alarm signal (DOl or D02).
Tu tali iter Preset Point
■ When the totalized flow reaches its preset count value, the
converter outputs a contact output signal (DOl or D02). j
Remote Zero Ad­
justment
■ Zero adjustment (on-stream at zero flow rate) can be started
by an external .signal (DT),
Fixed-value Output
Fixed current output and fixed pulse output can be used to
check a process loop ciroiiu An external signal (DI) can also
he used lo conlroJ this fixed-value output.
Converter Failure
Alarm
■ I’he converter outputs an alarm signal (DOl or D02) if an
error such as memory error or excitation circuit error occurs.
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