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83503001 Rev G
5.5.2. Resetting Activated Foldback Protection
There are four methods to reset an activated Foldback protection.
a) Press the OUT button. The power supply output is enabled and the Output Voltage
and Current will return to their last setting. In this method, the Foldback protection
remains armed, therefore if the load current is higher than the current limit setting,
the Foldback protection will be activated again.
b) Press the FOLD button to cancel the Foldback protection. The power supply output
will be disabled and the VOLTAGE display will show “OFF”. Press the OUT button
to enable the power supply output.
c) Turn the power supply output Off and then On using the SO control (refer to Section
5.7). In this method the Foldback protection remains armed, therefore if the load
current is higher than the output current setting, the Foldback protection will be
activated.
d) Turn the power supply Off using the AC On/Off switch, wait until the front panel
display turns Off, then turn the unit back ON again. The power supply output is
enabled and the Output Voltage and Current will return to their last setting. In this
method, the Foldback protection remains armed, therefore if the load current is
higher than the output current setting, the Foldback protection will be activated
again.
5.6.
Output On/Off Control
The Output On/Off Enables or Disables the power supply output. Use this function to make
adjustments to either the power supply or the load without shutting off the AC power. The
Output On/Off can be activated from the front panel using the OUT button or from the rear
panel J1 connector. The OUT button can be pressed at any time to Enable or Disable the
power supply output. When the output is disabled, the Output Voltage and Current fall to
zero and the VOLTAGE display shows “OFF”.
5.7.
Output Shut-Off (SO) Control via Rear Panel J1 Connector
Contacts 2, 3 and 15 of J1 (Fig.4-2, Item 5) serve as Output Shut-Off (SO) terminals. The
SO terminals accept a 2.5V to 15V signal or Open-Short contact to disable or enable the
power supply output. The SO function will be activated only when a transition from On to
Off is detected after applying AC power to the unit. (Thus, in Auto-Restart mode, the output
will be Enabled after applying AC power; even if SO is at an Off level). After an On to Off
transition it is detected, the SO will Enable or Disable the power supply output according to
the signal level or the short/open applied to J1. This function is useful for connecting power
supplies in a “Daisy-chain” (refer to Section 5.16). The SO control can also be used to
reset the OVP and Fold Protection (refer to Section 5.3 and 5.5 for details).
When the unit is shut-off by a J1 signal, the VOLTAGE display will show “SO” to indicate
the unit state. J1 contact 15 is the SO signal input and contacts 2 and 3, IF_COM, are the
signal return (connected internally). Contacts 2, 3 and 15 are optically isolated from the
power supply output.
The SO control logic can be selected by the rear panel SW1 Setup switch. Refer to Table
5-2 for SW1 setting and SO Control Logic.
SW1-5 setting
SO signal level
J1-2(3), 15
Power supply
output
Display
Down (default)
2-15V or Open
0-0.6V or Short
On
Off
Voltage/Current
“SO”
Up
2-15V or Open
0-0.6V or Short
Off
On
“SO”
Voltage/Current
Table 5-2: SO Logic Selection
