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 de- tails).
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 (con- nected 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 | Power supply | Display |
| J1-2(3), 15 | output | |
Down (default) | 2-15V or Open | On | Voltage/Current |
| 0-0.6V or Short | Off | “SO” |
Up | 2-15V or Open | Off | “SO” |
| 0-0.6V or Short | On | Voltage/Current |
Table 5-2: SO logic selection
5.8ENABLE/DISABLE CONTROL VIA REAR PANEL J1 CONNECTOR
Contacts 1 and 14 of J1 (Fig.4-2, item 5) serve as Output Enable/Disable terminals by switch or relay. This func- tion is Enabled or Disabled by the SW1 Setup switch position 9. Refer to Table 5-3 for Enable/Disable function and SW1 setting.
| SW1-9 setting | Enable/Disable Inputs | Power supply output | Display | ALARM LED |
| Down (Default) | Open or Short | On | Voltage/Current | Off |
| Up | Open | Off | “ENA” | Blinking |
| Short | On | Voltage/Current | Off |
| |
Table 5-3: Enable/Disable function and SW1 setting
CAUTION
To prevent possible damage to the unit, do not connect any of the
Enable/Disable inputs to the positive or negative output potential.
NOTE
Safe Start mode-If the Enable/Disable fault condition clears when units in safe start mode recov- ery is by pressing OUT button or by sending an ‘OUT 1’ serial command. Auto Restart mode-The output will return back ON automatically when the Enable/Disable fault conditions clears.
5.9 CV/CC SIGNAL
CV/CC signal indicates the operating mode of the power supply, Constant Voltage or Constant Current. The CV/CC signal is an open collector output with a 30V parallel zener, at J1-13, referenced to the COM potential at J1-12 (connected internally to the negative sense potential). When the power supply operates in Constant Volt- age mode, CV/CC output is open. When the power supply operates in Constant Current mode, the CV/CC signal output is low (0-0.6), with maximum 10mA sink current.
CAUTION
Do not connect the CV/CC signal to a voltage source higher than 30VDC. Always connect the CV/CC signal to voltage source with a series resistor to limit the sink current to less than 10mA.
5.10 PS_OK SIGNAL
The PS_OK signal indicates the fault condition of the power supply. PS_OK is a TTL signal output at J1-16, ref- erenced to IF_COM at J1-2, 3 (Isolated Interface Common). When a fault condition occurs, the PS_OK level is
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