GE Industrial Solutions FNW700R Series - Manual (Page 7)

Data Sheet
October 24, 2011 FNW700R Power Modules; DC-DC Converters
36 – 75 Vdc Input; 28Vdc Output; 700W Output
LINEAGE POWER 7
Safety Considerations (continued)
For all input sources, other than DC MAINS, where the
input voltage is between 60 and 75V
dc
(Classified as
TNV-2 in Europe), the following must be meet, if the
converter’s output is to be evaluated for SELV:
 The input source is to be provided with reinforced
insulation from any hazardous voltage, including
the ac mains.
 One V
I
pin and one V
o
pin are to be reliably
earthed, or both the input and output pins are to be
kept floating.
 Another SELV reliability test is conducted on the
whole system, as required by the safety agencies,
on the combination of supply source and the
subject module to verify that under a single fault,
hazardous voltages do not appear at the module’s
output.
All flammable materials used in the manufacturing of
these modules are rated 94V-0, or tested to the
UL60950 A.2 for reduced thickness.
The input to these units is to be provided with a
maximum 30 A fast-acting fuse in the unearthed lead.
Feature Description
Remote On/Off
Remote ON/OFF control is available as standard and
has positive logic remote On/Off mode only. The
converter will be active as long as a current Ion/off (1 to
5mA) is flowing into the ON/OFF+ (pin 4) and from the
ON/OFF- (pin 3), and inactive when no current is
flowing. Remote control pins are isolated up to 1.5 kV.
The voltage to drive this current can be derived from
the input voltage, the output voltage, or an external
supply with an appropriate current limit resistor. The
maximum forward current allowable without damage is
5 mA, and the maximum reverse current is 10mA. A
typical remote ON/OFF circuit is shown as Figure 10.
The current limit resistor (R1) is connected from Vin (+)
pin to ON/OFF + pin, an open collector or an equivalent
switch can be connected between ON/OFF - and V
I
(-)
pins to control ON/OFF operation. A 0 Ohm resistor
(R2) can be used if no open collector or switch used.
For 48Vin, an appropriate R1 value is recommended to
be 30Kohm (0.5W).
Figure 10. Circuit configuration for using Remote
On/Off Implementation.
Overcurrent Protection
To provide protection in a fault output overload
condition, the module is equipped with internal current-
limiting circuitry and can endure current limit for few
milli-seconds. A latching shutdown option is standard. If
overcurrent persists for few milli-seconds, the module
will shut down and remain off until the module is reset
by either cycling the input power or by toggling the
on/off pin for one second.
An auto-restart option (4) is also available in a case
where an auto recovery is required. If overcurrent
persists for few milli-seconds, the module will shut
down and auto restart until the fault condition is
corrected. If the output overload condition still exists
when the module restarts, it will shut down again. This
operation will continue indefinitely, until the overcurrent
condition is corrected.
Over Voltage Protection
The output overvoltage protection consists of circuitry
that monitors the voltage on the output terminals. If the
voltage on the output terminals exceeds the over
voltage protection threshold, then the module will
shutdown and latch off. The overvoltage latch is reset
by either cycling the input power for one second or by
toggling the on/off signal for one second. The
protection mechanism is such that the unit can continue
in this condition until the fault is cleared.
An auto-restart option (4) is also available in a case
where an auto recovery is required.
Output Voltage Programming
Trimming allows the user to increase or decrease the
output voltage set point of a module. Trimming down is
accomplished by connecting an external resistor
between the TRIM pin and the SENSE(-) pin. Trimming
up is accomplished by connecting external resistor
between the SENSE(+) pin and V
o
(+) pin. The trim
resistor should be positioned close to the module.
Be sure to use a zero resistor or short SENSE(+) and
V
o
(+) pins when the trim up function is not used.
If not using the trim down feature, leave the TRIM pin
open.