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Fan Stop/Thermal Alarm (J3 pin 5):
Logic signal goes low if the fan stops; or in the event of overheating, at least 10mS prior to a
thermal shutdown of the supply. Signal remains low until fault is cleared. If a thermal shutdown
has occurred, the input power must be re-cycled to restore output.
Input Power Fail Signal (J3 pin 6):
Following the loss of input power, this signal provides at least 5mS warning prior to any output
going outside of it's regulation band when adjusted to Vo nominal at full load. The signal goes
"Low" when input power is lost. Signal "High" on fault available as a special option.
Global Inhibit (J3 pin 8):
A TTL compatible signal will turn off all output modules, depending upon the setting of the
Inhibit/Select function (See below.) The outputs are less than 0.5V while inhibited at no load.
Inhibit/Select (J3 pin 10):
When open circuit, Global Inhibit is Active Low. When this input is shorted to signal common
(Pin 3), Global Inhibit is active high.
OUTPUT MODULE SIGNALS & FEATURES
Output module options are available only with single output modules. Logic Level signal
outputs are via open collector NPN transistors (40VDC/10mA max ratings) except the Module
Inverter OK signal which is 20VDC/4mA. Pull up resistors are required.
Signals are referenced to the -Remote Sense terminal. (J1 pin 10)
+Remote Sense (J1 pin 1- single output module, J2 pin 3 & 4 – dual output module):
Compensates for load cable drop from power supply to sense point (.25V per terminal.) To
meet regulation the remote sense must be connected to the load or locally to the power
supply.
Remote Voltage Adjust (J1 pin 2):
This input signal may be used for remote adjustment of the /- 10% of nominal via
external resistive or current input. Requires external potentiometer (10K ohms) b/-
remote sense terminals with the wiper to remote voltage adjust pin.
Margin (J1 pin 3):
Mar/- 5% of nominal output voltage. Requires an external switch (normally open,
SPDT) connected to the +/- remote sense terminals with switch common connected to Margin
input.
Current Sharing (J1 pin 4):
Active current sharing provides Load Sharing between two or more similar output modules to
within 10% of each output’s rated current. The current share node automatically disconnects if
a module inverter fault is detected. Modules with this option share current proportionally to
their maximum current ratings. Current sharing between modules is accomplished by
connecting J1 pin 4 of each module together. A single remote sense point must be used. The
individual output voltages must be set to within 1% of each other to ensure the outputs are
within a 2% capture window. Refer to Lambda application note AN-018 for additional details.
High Module Signal (J1 pin 5):
When outputs are connected in parallel and the current share option is employed, only the
module with the highest output voltage will have a logic high signal (useful for system
diagnostics). This is an open collector output signal.
