(2) Constant current adjustment by external voltage
¡
By applying a voltage externally to ITRM, output current for con-
stant current becomes adjustable.
When the ITRM terminal voltage is set at less than 2.5 V, the con-
stant current set value can be changed.
Output current [A] =
The voltage between
ITRM and -S[V] ×Rated output current [A] ...
2
2.5 [V]
¡
Do not set the external applied voltage of the terminal to -0.3 V or
less, and 5.0 V or more.
0.01
μ
F
4.7kΩ
10kΩ
ITRM
-S
5V
Fig.3.12 ITRM circuit
Note :
¡
If the output voltage becomes less than 5% of the rated voltage
during constant current operation, the output may become un-
stable.
3.11 Inverter operation monitor (IOG)
¿
TUNS300F/500F/700F
¡
By using the inverter operation monitor (IOG), condition of the in-
verter can be monitored.
The following
1
or
2
conditions make the IOG signal turns “H”
from “L” within 1 second.
1
Malfunction of inverter
2
Output voltage is rapidly dropped by adjusting output voltage
Specification of IOG is shown in Table 3.4.
Table 3.4 Specification of IOG
No.
Item
IOG
1
Function
Normal operation "L"
Malfunction of inverter "H"
2
Base pin
-S
3
Level voltage "L"
0.5V max at 10mA
4
Level voltage "H"
Open corrector
5
Maximum sink current
10mA max
6
Maximum applied voltage
35V max
3.12 Power good (PG)
¿
TUNS1200F
¡
By using PG, it is possible to monitor power supply whether
normal operation or abnormal operation. The PG signal is “Low”
when the power supply operates correctly. The signal turns to
“High” when the power supply stops.
¡
PG circuit is designed as shown in Fig.3.13.Sink current of PG is
1mA max.
¡
Circuit of the PG (PG,PGG) is isolated from input, output, FG and
various function terminals.
Notes when you use PG signal are shown below.
1
The PG signal is “High” when the output voltage is 20% or less
of the rated output voltage or 60% or less of the output voltage
setting value,
2
The PG signal is “Low” when the power supply operates during
constant current.
Table 3.5 Specification of PG
No.
Item
PG
1
Function
Normal operation “Low”
The power supply stops “High”
2
Base pin
PGG
3
Level voltage “L”
0.5V max at 1mA
4
Level voltage “H”
Open corrector
5
Maximum sink current
1mA max
6
Maximum applied voltage
50V max
100kΩ
0.1
μ
F
PG
PGG
Fig.3.13 Internal circuit of PG
3.13 Withstanding Voltage/Isolation Voltage
¡
When testing the withstanding voltage, make sure the voltage
is increased gradually. When turning off, reduce the voltage
gradually by using the dial of the hi-pot tester. Do not use a
voltage tester with a timer as it may generate voltage several
times as large as the applied voltage.
TUNS300F, TUNS500F, TUNS700F, TUNS1200F
AC-DC Power Supplies Bus Converter.Power Module Type
Instruction Manual
TUNS-28
July 27, 2020
