Hitachi L200 Manual Do Utilizador

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L200 Inverter
Oper
ations
and Monitor
ing
4–35
Internal Relay Output
The inverter has an internal relay output with 
normally open and normally closed contacts (Type 
1 form C). The output signal that controls the relay 
is configurable; the Alarm Signal is the default 
setting. Thus, the terminals are labeled [AL0], 
[AL1], [AL2], as shown to the right. However, you 
can assign any one of the nine intelligent outputs to 
the relay. For wiring purposes, the general terminal 
function are:
• [AL0] – Common contact
• [AL1] – Normally open contact
• [AL2] – Normally closed contact
The relay itself can be configured as “normally open or closed.” Parameter C036, Alarm 
Relay Active State, is the setting. This setting determines whether or not the relay coil is 
energized when its output signal is OFF:
• C036=00 – “Normally open” (relay coil is de-energized when output signal is OFF)
• C036=01 – “Normally closed” (relay coil is energized when the output signal is OFF)
Since the relay already has normally open [AL1] 
and normally closed [AL2] contacts, the purpose of 
the ability to invert the relay coil’s active state may 
not be obvious. It allows you to determine whether 
or not an inverter power loss causes the relay to 
change state.
 The default relay configuration is the 
Alarm Signal (C026=05), as shown to the right. 
And, C036=01 sets the relay to “normally closed” 
(relay coil normally energized). The reason for this 
is that a typical system design will require an 
inverter power loss to assert an alarm signal to 
external devices.
The relay can be used for other intelligent output 
signals, such as the Run Signal (set C026=00). For 
these remaining output signal types, the relay coil 
typically must NOT change state upon inverter 
power loss (set C036=00). The figure to the right 
shows the relay settings for the Run Signal output.
If you assign the relay an output signal other than 
the Alarm Signal,  the inverter can still have an 
Alarm Signal output. In this case, you can assign it 
to either terminal [11] or [12], providing an open 
collector output.
AL0
AL2
AL1
Inverter logic 
circuit board
AL0
AL2
AL1
Inverter logic 
circuit board
AL
C026=05
C036=01
Relay shown with inverter 
power ON, Alarm Signal OFF
AL0
AL2
AL1
Inverter logic 
circuit board
RUN
C026=00
C036=00
Relay shown with inverter 
power ON, Run Signal OFF