CB Svendsen FA-20, Руководство пользователя

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9.5 FA-20 Key stroke, serial meters and dial-back.
It is possible to activate serial reading of up to 3 serial meters through a key stroke. There
may only be mounted one meter pr. serial port. When the key in FA-20 is activated for more
then 1 second (programmable from the main station), the FA-20 will try to retrieve data first
from a serial meter connected port M1, hereafter a serial meter connected port M2 and at last
from a serial meter connected port “MULTI”.
After the keystroke the big green LED will blink shortly once every second while reading
possible meter on port M1 and twice every second while reading possible meter on port M2
and three times shortly per second while reading possible meter on port “MULTI”. If a meter is
not connected or of some reason cannot be read correctly by the FA-20 – then the big red
LED will light up for 3 seconds – just as the FA-20 gives up of getting an answer from the
meter.
If the key does not work or if not all 3 ports are tested by key stroke – then it is likely that it is
the main station who has commanded the FA-20 not to do a serial communication on the
questioned ports. (This can be relevant if FA-20 only is used for pulses). The installer can get
around this by switching off the FA-20 in 5 seconds – then the FA-20 will go into “engineer
mode” where all 3 ports are read on key stroke – whether the main station has asked the FA-
20 not to read one or more ports. “Engineer mode” ends automatically after 20 minutes of
“power failure”.
If FA-20 is coded to carry out a GSM-communication (dial-back) then FA-20 will try this after
any serial meters have been attempted to be read due to key stroke. The big green LED will
light constantly during the communication and in case of error the red LED will report the error
by a 3 second long flash.
Note: Automatic readout after power up.
Approximately 2-3 min. after power-up the FA-20 will normally begin to readout possible serial
meters which may be connected to the FA-20. This results in the same way as when the FA-
20 reads out the serial meter because of key stroke, that the big green LED flashes shortly
once every second by readout of possible meter on port M1 and shortly twice every second
by readout of possible meter on port M2 and shortly three times per second by readout of
possible meter on port MULTI. If a meter is not connected or for some other reason cannot be
readout correctly by the FA-20 – then the big red LED will flash for 3 seconds.
By keystroke there will only be tried once per meter – unlike when the FA-20 per routine or
after power up tries it-self, where there typically is used 1-2 retries (programmable from the
main station) in case the meter does not answer the first time.
Deactivation of communication with serial meters.
It is possible for the main station to deactivate the readout of serial meters both in connection
with keystroke and in connection with power up. This can be relevant in connection with FA-
20, who alone is used for pulse counting. This can seem unfortunate if an installer later has to
install a new extra meter and for example M2 no longer can be activated via keystroke. That
is why there is made an exception “Engineer mode”, so that a keystroke in the first 20 minutes
after power up ALWAYS looks for meters on all 3 serial ports if at least one port is enabled. If
all ports are disabled for example if only pulse are received, then key stroke does not enable
serial readings in the first 20 minutes after power up.
Specifications are subject to revision without notice.