Local Operation
Series 2268 850 Watt DC Power Supplies Reference Manual
50
2268S-901-01 Rev. A / January 2015
RESETTING ACTIVATED FOLDBACK PROTECTION
To reset activated and latched foldback protection, press and hold the rotary Adjust/Enter
control for approximately 3 seconds.
The SCPI command (s) for these instructions are:
[:]OUTPut[<channel>]:PROTection:CLEar
USING OVER VOLTAGE PROTECTION (OVP)
The OVP circuit protects the load in the event of an analog programming error, an incorrect
voltage control adjustment, or a power supply failure. The OVP circuit monitors the output
voltage at the output of the power supply and will disable the output whenever a preset
voltage set point is exceeded. You can set the preset voltage trip point by using the 9-position
mode control on the front panel or via one of the remote programming interfaces.
To prevent accidental tripping of the OVP while setting up, the firmware will prevent the
OVP set point from being less than 105% of the voltage set point when in local set point
control mode. When the power supply is in VAP mode for defining voltage set point the set
point limitation will be based on the VAP input signal level. The user should note it is
possible to trip OVP in this mode if the OVP is configured when the analog programming
source is off.
When the user attempts to configure an OVP setpoint that is less than 105% of the voltage set
point via the front panel the set point will stop allowing the value to decrement. If the user
attempts to configure an OVP set point that is less than 105% of the voltage set point via
SCPI a -221, “settings conflict error” will be pushed onto the error queue.
Defining the OVP Set Point
To define the OVP set point:
1.
Turn the power supply On.
Ensure the voltage is lower than the desired set point.
2.
Set the output to the desired voltage.
OVP can be set without setting desired output voltage first.
3.
Turn the 9-position mode control to the PRT position.
Προ ΟΥΠ
is displayed.
4.
Press the rotary Adjust/Enter control.
5.
Turn the rotary Adjust/Enter control to set the upper limit protection. See “Coarse
and Fine Adjustment Modes” on page 31.
Important:
The OVP range is variable from VSET +5% to VMAX +25%.
6.
Once the desired value has been set, press the rotary Adjust/Enter control to
commit the setting.
The SCPI command (s) for these instructions are:
[[:]SOURce[<channel>]]:VOLTage:PROTection[:OVERvoltage] [:LEVel]
If the output is between OVP
set
and -5%, an OVP warning message is possible when in
APG mode.
Summary of Contents for Keithley 2268 Series
Page 102: ......