JLG X20JP - X600AJ Service Manual - Manual (Page 294)

SECTION 6 - JLG CONTROL SYSTEM
6-78 – JLG Lift – 3121623
Once the alarm is detected the charger waits for 10 sec-
onds, after which it checks if the voltage has dropped
below 1 Volt/cell. After that this condition is satisfied for 1
second, the charger is ready for the connection of a new
battery, which will be detected above 1.5 Volt/cell. During
all this time, the display (where present) will show A13.
CB – firmware version 0.25, CB9 – firmware version 0.44
(or higher)
The detection algorithm is unchanged. What actually dif-
fers is the behaviour of the charger once the alarm is
detected. The charger do not have the 10 seconds time-
out, thus as soon as the voltage drops below 1 Volt/cell
(which requires some seconds due to the capacitor dis-
charge) the charger recognizes a complete disconnec-
tion. At this point the display (if present) will stop showing
A13 and will show just three red dots, meaning that the
charger is ready to detect a new battery. In this perspec-
tive, the A13 alarm is no longer a “battery disconnected”
alarm, but rather a “bad connection” alarm. Also, through
the display it is possible to understand when a new bat-
tery can be connected.
CB6
Temporary alarm. Differently from the CB, CB9 and QL
version, the battery disconnection detection algorithm do
not depends on the charging phase. A disconnection is
detected if the measured voltage is below 1.4 V/cell and
the voltage had decrease of at least 1/10 in the last 2 sec-
onds. Once the disconnection has been detected the
charger stops and after 7 seconds waits for the battery
voltage to raise above 1.7 Volt/cell before being able to
restart a new charge.
The figure below summarizes what happens (indepen-
dently from the firmware versions), from the charger’s
point of view, in a valid battery disconnection procedure.
(Note: the threshold voltages vary depending on firmware
version – the values shown are valid only for NG1/NG3,
G9).
Figure 6-57.
T1: Battery disconnected (alarm detected
T1 – T2: Measured voltage drops with a capacitor dis-
charge characteristic. This phase lasts at least 10 seconds
in older firmware versions. Display shows A13.
T2: V < 1 Vpc. From now on, a new battery can be con-
nected. In the most recent firmware versions, the display
show s 3 red dots.
T3: a new battery is recognized
It’s very important to understand the difference between a
correct battery disconnection, and a bad connection situ-
ation, which may lead to a blocking state. The figure
below shows what happens, from the charger’s point of
view, in a bad connection situation.
Figure 6-58.
T1: a battery disconnection is detected
T2: the connection has some problem, e.g. the connec-
tion is partially interrupted.
T3: the connection problem disappears.