Operation From Dc24V Contact Input - Hitachi SAMURAI Series Service Manual

2 Control Functions
Control functions on the module

2.1.13 Operation from DC24V contact input

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Outline
The procedure to control operation from the DC24V contact of the local central controller is shown below.
• Level input
• Pulse input (1 switch)
• Pulse input (2 switches)
Arrange the settings and additional wiring necessary for each of them, as shown in the following sections. Available only
in remote mode during independent operation of the chiller unit.
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Level input
a. Signal aspect and basic sequence
For wiring
Time chart
?
N O T E
Level input indicates a continuation of switch ON status when the system is in operation as shown in the diagram above.
26 SMGB0120 rev.0 - 11/2017
Terminal
board
Section arranged as a local work
Run/stop switch (to be
prepared locally)
Alarm output (DC24V, less than 0.8A)
ON
Switch
OFF
Run
Chiller
unit
Stop
Relay coil for DC24V, etc. (to be prepared
locally) (The relay coil is powered on in
case of alarm) Do not connect a LED or a
relay of internal diode type.
Keep more than 5 minutes