LOK4240-2RLDG Datasheet, PDF (6/10 Pages) Power-One – LOS, LOR, LOK4000 Series Data Sheet DIN-Rail Mountable AC-DC (DC-DC) Converters

LOS, LOR, LOK4000 Series Data Sheet
®
DIN-Rail Mountable AC-DC (DC-DC) Converters
Auxiliary Functions
Adjustable Output Voltage (R input)
As a standard feature, the LOK units offer adjustable output
voltage by using the control input R. If the R pin is left open-
circuit, the output voltage is set to V_{o nom}. (see: Output data)
The R input is referenced to the secondary side of the
converter. Adjustment of the output voltage is possible by
means of either an external resistor or a voltage source.
a) Adjustment by means of an external resistor R_ext1:
Depending upon the value of the required output voltage,
the resistor shall be connected
either: Between the R terminal and Vo– to achieve an
output voltage adjustment range of approximately
V_o = 90 - 100 % V_{o nom}.(LOK4301, 4601 and 4801 types)
V_o
R_ext1
≈
4
kΩ
•
–––––––––
V_{o nom} – V_o
or: Between the R terminal and Vo+ to achieve an output
voltage range of approximately V_o = 100 - 110% V_{o nom} for
rectifier versions and 100 - 125% V_{o nom} for battery chargers.
(V_o – 2.5 V)
R_ext2
≈
4
kΩ
•
–––––––––––––––––––
2.5 V • (V_o/V_{o nom} – 1)
Table 4: Output Voltage OK signal
b) Adjustment by means of an external voltage V_ext between
Vo– and R terminal to achieve an output voltage adjustment
range of approx. 90 - 110% V_{o nom} (LOK 4301, 4601 and
4801 types), 93 - 117% V_{o nom} for battery chargers.
V_o • 2.5 V
V_ext
≈
–––––––––
V_{o nom}
Attempting to adjust the output below this range will cause
the converter to shut down (hiccup mode).
Note: Applying an external control voltage >3 V may damage the
converter.
JM075
L
Vo+
V_ref = 2.5 V ^{4 kΩ}
+
Control
logic
N
R_{ext 2}
R
+
R_ext1
V_ext
G
–
Vo–
Fig. 5
Output voltage control by means of the R-input
Output Voltage OK (D Output)
The D-output is referenced to Vo– and monitors the output
voltage V_o. If V_o drops below V_{o t}, the D-output will be disabled
(open-collector circuit). The circuitry works independently of the
input voltage and can therefore be used as battery-low indicator.
Conditions
V_{o t} setting
V_D V_o - V_{o t min}
V_o > V_{o t max}
I _D < 50 mA
LOK4001-2RLD
LOK4140-2RLD
LOK4240-2RLD
LOK4740-2RLD
Unit
min
max min
max min
max min
max
4.4
4.8 10.5
11.5 21
23 42
46
V
60
60
60
60
0.6
0.6
0.6
0.6
Battery Charging/Temperature Sensor
The LOK 4140/4240/4740 are designed to charge lead-acid
batteries. For optimum battery charging and extended life time
of the battery an external temperature sensor may be
connected to the R-input. The sensor should be mounted as
close as possible to one of the poles of the battery.
Depending upon the cell voltage and the temperature coefficient
of the battery, different temperature sensors are available. For
more information please see: Temperature Sensors (Accessory
Products on the Web Site) or contact Power-One.
+ – _{Sensor Sensor Temperature}
wires cable sensor
R ^white
Vo+
Fuse
Vo–
brown
green
+
–
Battery
Fig. 6
Voltage setting by a temperature sensor, wiring diagram
If no sensor is used, the float charge voltage should be
adjusted with a suitable resistor connected to the R input (see:
Adjustable Output Voltage).
Cell voltage [V]
2.45
2.40
2.35
06123b
V_{o max}
2.30
2.25
2.20
2.15 ^Vo safe
2.10
–20 –10 0
10 20 30 40 50 °C
Fig. 7
V_C = 2.27 V, –3 mV/K
V_C = 2.23 V, –3 mV/K
V_C = 2.27 V, –3.5 mV/K
V_C = 2.23 V, –3.5 mV/K
Float charge voltage for defined temperature coefficients.
BCD20035-G Rev AB, 23-Jun-2011
Page 6 of 10
www.power-one.com