5 Functions
5-3. External output
- 29 -
FP-300AGZS
SK: Surge absorbing filter
- Understanding of alarm contact on inductive load -
If inductive load is used at the alarm contact, the following errors may occur easily because very high
counter electromotive voltage is generated.
The relay contact melts and disables the contact activation.
High voltage entered inside of the indicator damages any number of electric parts.
Resulted large noise makes CPU out of control and behave abnormally.
Unexpected noise may enter the contact regardless of inductive load, thus posing a risk of above errors.
To avoid above errors, the following preventive measures should be taken.
In principle, inductive load should not be used. (Never use a fluorescent lamp, motor, etc.)
External contact amplification is required to use inductive load. However, because an external relay coil
is also regarded as inductive load, use a relay operated at low voltage (up to 100 VAC) and protect with
an appropriate surge killer.
Make sure to protect the contact with an appropriate surge killer to directly control a small inductive load.
The rated specification of the contact in this case is 50% of resistance load or less.
100 VAC
0.25 A or less
Followings are examples of inductive load.
Revolving light, external relay, buzzer, siren, fan, fluorescent lamp, motor, etc.
Alarm contact
Power supply
Coil
Power supply
Load
Relay
(Low voltage relay)
