Riken Keiki GD-K71D, Operating Manual

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31
６．KIND OF ALARM AND ITS FUNCTION
６－１．Kinds of alarms
There are two kinds of gas alarm and trouble alarm.
Gas alarm : When the detection gas reaches to preset alarm level or exceeds it, this starts
to function. 《Non-latched mode》
* Trouble alarm : Trouble is detected in the detector and it gives an alarm as trouble alarm.
Except system trouble “E-00”, it is non-latched. When return to normal from
trouble condition, it starts again from the performance «Initial clear» after
power on. [See “8. TREATMENT AT ABNORMAL CASE”]
６－２．Gas alarm
６－２－１．Gas alarm action
(1)Display
①Gas concentration display
When exceed detection range, LED display shows “∩∩∩∩”.
②Power light (POWER : Green)
It keeps continuous lighting.
③Alarm light (ALM1 : Orange), (ALM2 : Red)
There are two alarm levels. When the reading goes to alarm preset level or
exceeds it, this turns to on.
(2)External output
①4～20mA output
Electric current in proportion to gas concentration is output. In case of over scale,
the maximum output is approx 22mA.
②Alarm contact
When gas concentration reaches preset alarm level or exceeds it, the relay
contact for outer alarm works.
Relay contact is a non-latched condition. It returns automatically when gas
concentration decreases under preset alarm level.
Alarm delay time(6 sec.)
Alarm delay time(6 sec.)
Alarm light (ALM 1)
Alarm contact (Terminal 7，8)
Alarm light （ALM 2）
Alarm contact (Terminal 9，10)
ALM2 Alarm level
ALM1 Alarm level
Conce
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＊ NOTE
Alarm levels are adjusted at 1/3(1st alarm) and 2/3 (2nd alarm) of full scale as
standard.
To prevent error of performance, this is provided with 6 second alarm delay time.