AMETEK XG Family Programmable DC - Manual (Page 79)

Local Operation
M370430-01 Rev E 3-33
3
Defining the Polarity of the External Shutdown Signal
1. Turn the 9-position mode control to the PRT position or press
the rotary Adjust/Enter control if the control knob is already
at the PRT position.
is displayed on the output voltage display.
2. Turn the rotary Adjust/Enter control until is
displayed.
3. Press the rotary Adjust/Enter control to display
(shutdown on logic 0) or (shutdown on logic 1).
4. Press the rotary Adjust/Enter control to commit the desired
polarity setting.
For example: If you set the shutdown logic to 1 ( ) and apply a
logic high (greater than 1.2 Vdc) to pin J3.12 relative to pin J3.6 on
the ISOL connector, the power supply will shut down. Conversely,
if you set the shutdown logic to 0 (
), the power supply will
only operate when you have a logic high (greater than 1.2 Vdc) to
pin J3.2 relative to pin J3.6.
Important: There is an internal pullup resistor inside the shutdown circuit so
the shutdown polarity should be set to 0 if it is not being used.
The SCPI command (s) for these instructions are:
[:]OUTPut[<channel>]:POLarity
Loop Protection (version 2.21 and higher)
The Loop Protection feature can be used to enable or disable multiple
units in daisy chain configuration through the AUX Output and Isolated
Analog Programming Connector, J3. Up to four units (example, Units
#1 through #4) can be configured in Loop Protection; if one of the units
is experiencing a fault condition, other units in the same loop will
disable their output simultaneously. This is achieved by connecting Unit
#1’s MAIN_PS_GOOD to Unit #2’s SD (Shutdown Main O/P) and
continues until Unit #4’s MAIN_PS_GOOD is fed to Unit #1’s SD
(Shutdown Main O/P). Common applications include single master
controlling multiple slave units as a system On/Off. In addition, any
fault from either operating unit will cause the system to disable.
The Loop Protection can be enabled or disabled locally using the front
panel 9-position mode control, or remotely using a SCPI command.
Important: While Loop Protection is enabled (ON), the external shutdown
function will be automatically set to low active. When Loop Protection is
disabled (OFF), the external shutdown function will be set to the user’s last
setting.