RKI Instruments GD-70D Series, Руководство по эксплуатации

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GD-70D
4-4 Proper use of alarm contact
The alarm contact of the detector is used to transmit signals to activate an external buzzer, alarm lamp or
rotating lamp. Do not use the detector for controlling purpose (e.g., controlling the shutdown valve).
The specifications for the alarm contact of the detector are based on the resistive load conditions. If
inductive load is used at the alarm contact, the following errors will occur easily because counter
electromotive force is generated at the contact.
•
Deposition, defective insulation or defective contact at the relay contact
•
Damage of any electric parts due to high-voltage generated inside the detector
•
Abnormal operations by an out-of-control CPU
If load is to be activated, appropriate measures must be taken to stabilize the operation of the detector and
protect the alarm contact referring to the following information.
•
Relay it with an external relay at 100 VAC or lower (contact amplification). At the same time, the surge
absorbing part, SK1, suitable for the specifications must be attached to the external relay.
•
In addition, the surge absorbing part, SK2, must be attached to the loaded side of the external relay if
necessary.
•
It may be recommended that the surge absorbing part be attached to the contact for certain load
conditions. It must be attached to an appropriate position by checking how the load is activated.
GD-70D
SK1 SK2
Alarm
Contact
Power
supply Power
supply
External relay
(low voltage relay)
* SK1, SK2: Surge absorbing parts
CAUTION
•
The b contact (break contact) under de-energized state may be opened momentarily by a physical
shock, such as external force.
•
When the b contact is selected for the alarm contact, take appropriate actions to prepare for a
momentary activation by adding signal delay functionality (approximately one second) to the
receiving side of the b contact.
CAUTION
•
In principal, do not activate inductive load at the alarm contact of the detector. (In particular, never
use the inductive load to activate a fluorescent lamp or motor.)
•
If inductive load is activated, relay it with an external relay (contact amplification). However, because
the coil of an external relay also involves inductive load, select a relay at a lower voltage (100 VAC or
below), and then protect the contact of the detector with an appropriate surge absorbing part, such
as a CR circuit.
C
oi
l
Load