American Magnetics 12100PS DC Power Supply (CE-Marked) - Manual (Page 35)

OPERATING MANUAL LOCAL OPERATION
Release 2.0 (98/06) 3-5
3.4 Using the Shutdown Function
Use the Shutdown function to disable or enable the supply's output so that you can make adjustments to either
the load or the power supply without shutting off the power supply. Activate this function from the front panel at
any time by using the STANDBY switch. You can also activate it via remote control through the rear panel J2
Programming and Monitoring connector, using a transistor-transistor logic (TTL) compatible input. The input
lines for the Shutdown circuit are optically isolated.
3.4.1 STANDBY Switch
The STANDBY switch is a press ON/press OFF switch located on the power supply's front panel. See the front
panel diagram in Section 2.3. Push the switch to its IN position to activate the Shutdown circuit. The output
voltage and current to fall to zero and the red S/D (Shutdown) LED turns on. Push the switch once more to reset
it to its OUT position and resume normal power supply operation.
3.4.2 Controlling the Shutdown Function via the J2 Connector
The shutdown circuit uses a TTL-compatible signal to disable or enable the power supply output. Make
connections for TTL signals at connector J2, located on the unit’s rear panel. Set rear panel switch SW1-7 to
select signal logic. See Section 4.2 for more information about making J2 connector and SW1 switch changes.
To activate the shutdown function:
1. Turn OFF the power supply.
2. Connect the TTL signal source to J2 connector terminal 15 (TTL Shutdown Input/positive) and
terminal 14 (TTL Shutdown Return).
3. Set switch SW1-7 to select the desired circuit logic as set out in Table 3.4-1.
4. Turn on the power supply. The power supply will operate as described in the " Supply Output
Condition " column in Table 3.4-1, according to the logic you select and the level of the input signal.
The S/D (Shutdown) LED on the front panel turns on when the Shutdown circuit is activated.
Table 3.4-1 Switch Settings for TTL Shutdown Circuit Logic
Switch SW1-7 Setting TTL Signal Level Supply Output Condition S/D LED
OFF (Active low, default) HIGH OFF ON
LOW ON OFF
ON (Active high) HIGH ON OFF
LOW OFF ON
Notes:
1. If switch SW1-7 is ON but there is no signal applied, the S/D LED turns on and the power supply will
not provide an output until the HIGH TTL signal level is applied.
2. The rear panel SW1 switch is marked with the word OPEN on its upper surface. Any of the eight
switches on SW1 is OFF when it has been flipped up to break contact, ON when flipped down to close
contact.