14
HSF(A) 600W 040215
NOTE: Unlike earlier (non A) HSF 600W models, –PF and –RC are connected together
and cannot be isolated from each other. This return is connected to the power sup-
ply –OUTPUT when position 4 of SW1 is set to ON (factory default). If it is neces-
sary to isolate the –PF and –RC from the power supply output, set position 4 of
SW1 to OFF.
FIGURE 10. DIP SWITCH SETTINGS FOR OPTICALLY COUPLED LOGICAL ALARM
The logic alarm circuit is a diode transistor optical coupler (see Figure 11). The transistor is nor-
mally conducting. When the alarm is activated upon detection of power loss, overvoltage, fan
fault, overtemperature or overcurrent condition, the transistor cuts off and the collector emitter cir-
cuit is open. Figure 12 is a timing diagram of the power fail signal.
The default state of the alarm is logic low. The sink current for the optocoupler is 50mA maximum,
the maximum collector to emitter saturation voltage is 0.40 Volts, and the collector to emitter volt-
age is 40 volts maximum. The +PF signal is isolated from the AC input and DC output. The –PF
signal (in common with –RC) is connected to –OUTPUT when position 4 SW1 is set to ON (fac-
tory default). It is possible to isolate both –PF and –RC from –OUTPUT by setting SW1 of position
4 to OFF.
FIGURE 11. OUTPUT ALARM CIRCUIT OPTICALLY ISOLATED
3043770
5
5 +PF
+PF 5
5
SW1
SW2
OFF
ON
OFF
ON
USE N.O. AND N.C CONTACTS
(FACTORY DEFAULT)
OF INTERNAL RELAY
A
LOGICAL ALARM
USE OPTICALLY-COUPLED
B
(+PF AND -PF)
5
SW1
5
SW2
OFF
ON
ON
OFF
+PF 5
5 +PF
TAB
