The Kepco HSF-1UR 100 Watt Series hot swappable, high
frequency switching, plug-in power supplies with built-in
power factor correction (PFC) employ forward conversion
and are designed to operate in a fault tolerant power system with either a-c or d-c input. A thermistor soft-start circuit limits start-up surge; an input fuse (3A, 250V) protects
against shorts. Built-in OR-ing diodes (all models) and a
forced current share circuit (all models except 3.3V) allow
configuration of all models for hot-swap and parallel-redundant N+1 operation.
The heart of the HSF-1UR Series is a Kepco RTW power
supply allowing them to weigh less and have improved efficiency (input current) specifications over the older HSF-1U
Series. There are three options available: C, X and Y. Features for all models are the same except as follows: C
option (-1URC) models include a current sensing resistor,
allowing external current monitoring within ±10% (contact
Kepco if greater accuracy required). X option (-1URX) models have remote control, the ability to turn the unit on and
off from a remote location. Y option models (-1URY)
include both current monitoring and remote on-off capabilities.
HSF-1UR
100W SERIES
These power supplies are designed to be used with
Kepco’s Series RA 19-1U rack adapters. The RA 19-1U
rack adapter accepts up to four 50-, 100- or 150-Watt units
(see Figure 1). All input/output connections are through a
24-pin connector that plugs in to the rack adapter. All external connections are made through the rack adapter (refer
to the RA 19-1U manual which is available for free download at:
www.kepcopower.com/support/opmanls.htm#ra19-1u
Seven models may be selected for outputs of 3.3, 5, 12, 15,
24, 28 or 48V (see Table 1).
When the input is cut off, the output is maintained for 20
milliseconds minimum. If the power supply shuts down due
to an output overvoltage condition, it is then necessary to
wait 60 seconds minimum before turning the unit on again.
EMI filtering is designed to meet FCC Class B rating and
VDE 0871 Class B rating. Table 1 contains specifications
that vary for each model of the HSF-1UR 100 Watt Series.
Specifications common to all models are listed on page 4.
TABLE 1. OUTPUT RATINGS AND SPECIFICATIONS, HSF-1UR 100W SERIES
(1) Unless otherwise noted, specifications are identical for all options.
(2) Forced current Share not available for 3.3V Models.
(3) Derates same as Output Power.
(4) See power rating curve, Figure 4. Exceeding maximum power rating may result in
oscillation or a drop in output current or voltage.
KEPCO, INC. 131-38 SANFORD AVENUE FLUSHING, NY. 11355 U.S.A. TEL (718) 461-7000 FAX (718) 767-1102
(5) C and Y Models only (see “Current Monitor.” on page 2 for details).
(6) Natural convection cooled; see Figure 5.
HSF 24-4.2-1UR
(1)
HSF 28-3.5-1UR
(1)
HSF 48-2-1UR
(1)
PS2PS1
3042496
FIGURE 1. HSF-1UR 100 WATT POWER SUPPLIES (4) INSTALLED IN RA 19-1U RACK ADAPTER
II — FEATURES
FRONT PANEL ACCESS. The front panel provides a
power ON/OFF switch controlling input power and a “VDC
ON” light which indicates when the unit is operating.
NOTE: The ON/OFF switch must be set to OFF before
removing unit from rack adapter. The front panel “MAS-
TER ON” LED lights when 1) the unit operates independently, or 2) the unit is used in parallel redundant
configurations while a) the output is less than 10% of
nominal or b) the output is within 10% to 100% of nominal
and the unit is functioning as a master. In parallel redundant configurations, the module with the highest voltage
functions as the master. The other units are slaves, and
track the output voltage of the master. Refer to CurrentShare Bus (CSB) on page 3 for details. (For the 3.3V
model, the “MASTER ON” LED has no function and is
always off.) The front panel Vadj trimmer provides adjustment of the output voltage within the limits specified in
Table 1; test points connected to the +S and –S lines are
available at the front panel for measuring the output.
BUILT-IN OR-ING DIODES. OR-ing diodes allow
configuration of all models for hot-swap and parallelredundant N+1 operation where current distribution is not
equal and the idle unit takes over in the event of failure.
FORCED CURRENT SHARE CIRCUIT. (Not available on 3.3V model). When units are configured for N+1
parallel redundant operation, it is desirable (but not
required) for current to be divided equally among the paralleled supplies. When the CSB (forced Current Share Bus)
lines of paralleled HSF-1UR units are connected together,
the load current is forced to divide equally between all paralleled units; units operate at less than maximum, reducing
stress and increasing reliability of the system. If one unit
fails, the remaining units will continue to supply the load,
and the load current will be divided equally among the
remaining operating units. The failed unit is automatically
isolated from the circuit by a built-in isolation diode. Refer
to Current Share Bus (CSB) on page 3 for details.
PS3
PS4
CURRENT MONITOR. Current monitor (C and Y
models only) is via ±IMON assigned to pins of the RA 19(X)B I/O connector. Monitored Output Current (Amps) =
Voltage drop across R
R
is the sum of RS (see Table 1) + trace resistance to
EQ
(mVolts) / REQ (mOhms) where
EQ
point where current monitor is connected, approximately
4mOhms. The voltage drop across R
is measured
EQ
across ± IMON pins (requires millivoltmeter, range 0 to
250mV). Accuracy is ±10%; contact Kepco if greater
accuracy is required. There is no isolation between
±IMON, alarm circuit and d-c output. Refer to the applicable RA 19-1U Manual for details.
ALARM CIRCUIT. The HSF-1UR includes an isolated
internal relay offering normally closed and normally open
contacts referenced to an isolated common. These contacts may be used to configure “close on failure” or “open
on failure” alarm circuits. (Refer to the RA 19-1U Manual
for alarm configurations for multiple HSF-1UR power supplies.)
KEYING. Keying of the HSF-1UR is established at the
factory (see Figure 2). The output voltage determines
which key pins are installed. When the proper holes in the
rack adapter are blocked by keying screws installed by the
user, only a power supply of the correct voltage can be
inserted in the rack adapter slot. (Refer to the RA 19-1U
Manual for rack adapter keying instructions.)
REMOTE ON-OFF. Remote on-off (X and Y models
only) is via ±RC assigned to pins of the RA 19-1U I/O connector: off = no voltage, short circuit, or 0 to 0.8V, on = 4.5
to 12.5V (or 12.5 to 24.5V via 1.5K Ohms). To reverse onoff polarity contact Kepco. There is no isolation between
±RC, d-c output and alarm circuit. Refer to the RA 19-1U
Manual for details.
FIGURE 2. REAR CONNECTOR PIN ASSIGNMENTS
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CONNECTIONS: The 24-pin I/O connector (Figure 2)
mates with the corresponding connector in the RA 19-1U
Rack Adapter. All external connections are made at the
rack adapter (see Rack Adapter Manual).
(+) SENSE, (–) SENSE: These lines are provided to com-
pensate for voltage drops in the load connecting wires. The
Sense lines must be connected to their respective (+) and
(–) output terminals, either at the load or at the rack
adapter (see Rack Adapter Manual). The connection
ensures the most accurate error tracking.
NOTE:
The Sense lines must be connected for the
HSF-1UR Power supply to work properly!
Compensation per lead = (min. overvoltage - max.adjustment range)/2); refer to Table 1. Compensation for 3.3V
Model is 0.1V per lead. Higher compensation values are
possible if output voltage is decreased below the maximum
adjustment range shown in Table 1. Load wire length
should not be more than 16.4ft. (5m). Transient recovery
specs may not be met when remote sensing is used. To
prevent oscillations and premature tripping of overvoltage
protection, install one electrolytic (not tantalum) capacitor
(470mF min) between +S and +V and one between ±S terminals.
• Maximum difference among output voltages of
paralleled units: 250 mV
• Minimum difference among output voltages of paralleled units: 25 mV
NOTE: Current share requirements stated above may be
extended to units located in adjacent racks.
ALARM: The Alarm NC (normally closed) - Open on Fail-
ure and Alarm NO (normally open) - Close on Failure lines
are relay contacts referenced to Alarm Common. If the unit
fails, the path between Alarm NC - Open on Failure and
Alarm Common opens, the path between Alarm NO - Close
on Fail and Alarm Common is a short circuit. Figure 3 illustrates typical Close on Fail and Open on Fail circuits to give
a failure indication if any one of a number of power supplies
fail; refer to RA 19-1U manual for complete information
regarding other configurations.
OUTPUT (+), OUTPUT (–): HSF-1UR power supply d-c out-
put.
INPUT POWER: Line (either a-c or d-c source power), Neu-
tral and Ground (chassis)
CURRENT SHARE BUS (CSB): (Not available on 3.3V mod-
els.) Connecting the CSB lines of HSF-1UR power supplies
operating in a parallel configuration causes output current
to be shared equally. (See Rack Adapter Manual for additional information on parallel configurations.). For current
sharing to work properly the outputs of all paralleled units
must be within 250 mV (max) of each other and each unit
must be operating at between 10% to 100% of rated output. If current to the load goes below 10% for each unit in
current share mode, all MASTER ON lights may go on (see
load effect specifications); this indicates that forced current
share is no longer working, units are simply in current
share mode. (If forced current sharing at less than 10%
nominal current per supply is needed, contact Kepco application engineering.) Remote sensing is recommended. For
master/slave operation to work properly each unit should
be adjusted to 40 mV (optimum) less than the next paralleled unit (unit 1 is adjusted to VOUT, unit 2 to VOUT –
40mV, and unit 3 to VOUT – 80mV, etc. If the master fails,
unit 2 will become the new master). The 40 mV difference
can be reduced to a minimum of 25 mV as needed to parallel many units and still keep all units within 250 mV of each
other. Adjust the outputs using Vadj trimmer on front panel.
• Optimum difference among output voltages of paralleled units: 40mV
FIGURE 3. TYPICAL ALARM CIRCUIT DIAGRAMS
Units are shipped so that the alarm will trip and shutdown
will occur upon overvoltage, open sense line and fan failure
(fan failure shutdown can be disabled, see “Cooling:” onpage 4 and Figure 7). The alarm will also trip upon undervoltage, however shutdown may not occur, depending on
the load. After shutdown occurs, a 60 second delay (minimum) is required before turning the unit on again.
Forced shutdown upon fan failure (not applicable to 3.3V
Model) can be disabled by installing a jumper, Kepco P/N
172-0382 (Digikey P/N A26231-N) as shown in Figure 7.
This allows the unit to continue to operate with the fan inoperative (see Figure 4 for safe operating conditions); the
alarm signals noted above will report an alarm condition,
and the VDC ON indicator will either light red (fan supply
voltage missing) or flicker between red and green
(mechanical failure). If the jumper is installed, the user is
responsible for either reducing the load to within the specifications given in Figure 4, or shutting down the unit using
the alarm signals provided.
KEPCO, INC. 131-38 SANFORD AVENUE FLUSHING, NY. 11355 U.S.A. TEL (718) 461-7000 FAX (718) 767-1102
The following specifications apply to HSF-1UR 100 Watt
Series models (also refer to Table 1). Other models are
also available; consult your Kepco representative for their
specifications.
INPUT:
Voltage: 100-120V a-c, 200-240V a-c nominal;
Range 95-264V a-c; d-c range: 125-370V d-c.
Frequency: Nominal 50-60 Hz; Range 47-440Hz
(from 66 to 440Hz leakage current exceeds UL/
VDE safety spec. limit).
Initial Turn-on Surge: (cold start 25 °C, first surge
only, not including the current flow into the EMI filter):
@100V a-c rms, 14A typ.,
@200V a-c rms, 28A typ.
Brownout Voltage: 85V a-c, 110V d-c
Switching Frequency: 135KHz typical, PFC boost
converter: 80KHz typical, nominal load
STABILIZATION:
Source Effect:
95-132V a-c or 190-265V a-c:
0.3% typ.; 0.6% max.
3.3V Model 5mV typ., 10mV max.
Load Effect:
12V-48V models: 0.5% typ.; 1.2% max.,
3.3V, 5V models: 1.5% typ.; 2% max.
Temperature Effect, Range -10
0.5% typ.; 1.0% max.
Combined Effect (source, load, temperature):
0.9% typ., 1.8% max.
Time Effect (drift): (1/2 to 8 hr. at 25°C)
0.2% typ., 0.5% max.
RECOVERY CHARACTERISTICS: A step load
change from 50% to 100% produces less than +
excursion. Recovery occurs to within +
setting in <2 ms (load change t
than 50µsec).
START-UP TIME:
400 ms. typ., 500 ms. max. (100V a-c),
200 ms. typ., 300 ms. max. (240V a-c),
ACCEPTABLE LOAD CAPACITANCE: (Start-up
time is affected.)
10,000
µF max.
1.5A rms max;
o
to 50oC:
1% of the original
or tf equal to or greater
r
4% output
HOLDUP TIME: 35 ms. typ., 20 ms. min.
DIELECTRIC STRENGTH: (at 15 to 35°C ambient,
10 to 85% relative humidity):
Between input and output: 3KV a-c for one minute,
cutout current 10ma.
Between input and ground: 2KV a-c for one minute,
cutout current 10ma.
Between output and ground: 500V a-c for one min-
ute, cutout current 20ma.
INSULATION RESISTANCE: Between input and
ground, output and ground, input and output, ±RC terminals and input, ±RC terminals and output: 100
Megohms min. (500V d-c).
LEAKAGE CURRENT:
0.13mA typ, 0.19mA max at 120V a-c and 60 Hz
(operating in conformance with Den-An).
0.30mA typ, 0.45mA max at 240V d-c and 60 Hz
(operating in conformance with IEC 950 and
UL1950).
SAFETY: Certified to UL 60950-1, 1st Edition, 2007-1031 (Information Technology Equipment - Safety - Part 1:
General Requirements) and CSA C22.2 No. 60950-1-03,
1st Edition, 2006-07 (Information Technology Equipment Safety - Part 1: General Requirements). Units are CE
marked per the Low Voltage Directive (LVD), 2006/95/EC
(LVD) and 2004/108/EC (EMC). [The standards do not
apply with either DC input operation or with a-c input frequency above 66Hz.]
RoHS COMPLIANCE: RoHS 5 of 6 compliant to EU
directive 2011/65/EU if used as component within telecommunication systems.
COOLING: Natural convection for 3.3V model; 5-48V
models use forced convection, ball-bearing fans, life
expectancy 50,000+ hours. Natural convection can be
used for 5-48V models if the load does not exceed the limits specified in Figure 4). Simply disconnect the fan and
install jumper J1 (see Figure 7); the alarm signals
described above are disabled and VDC ON lights red;
overvoltage and open sense line conditions still force unit
shutdown. Contact Kepco’s Application Engineering for
full-featured natural convection-cooled units.
EMI: Designed to meet FCC Class B (100-120V a-c)
and VDE 0871 Class B (220-240V a-c).
VIBRATION: (non-operating, one hour on each one of
the three axes):
5-10 Hz, 10 mm amplitude;
10-55 Hz, 2g acceleration.
KEPCO, INC. 131-38 SANFORD AVENUE FLUSHING, NY. 11355 U.S.A. TEL (718) 461-7000 FAX (718) 767-1102
6 and insert HSF-1UR power supply in selected slot until
power supply front panel is flush with rack adapter chassis
and secure with two front panel mounting screws.
CAUTION: Do not overtighten these screws: max.
torque is 2 in.-lbs (0.23 N x m).
CONNECTIONS. All connections are made at the rear
panel of the RA 19-1U Rack Adapter (see RA 19-1U
Operator Manual). Connect the load to the applicable ±
DC OUTPUT terminals. AC input power is applied via two
V — OPERATION
Turn the unit on using the front panel POWER switch (see
Figure 6). CAUTION: DO NOT repeatedly toggle the
POWER on/off switch as this may cause unit to fault.
When output voltage is available, the VDC ON LED is on
(green). For 100W and 150W 5V through 48V models the
VDC ON LED lights red to indicate a fan malfunction. The
100W 3.3V model and all 50W models use convection
cooling and do not include a fan.
While monitoring output voltage at the front panel test
points, the Output Voltage Adjust trimmer allows adjustment of the output voltage.
INPUT POWER terminal blocks: one supplying slots 2
and 4, the other supplying slots 1 and 3. Make sure to
connect the AC input Neutral, Line and Ground wires to
the respective terminals of the terminal blocks.
REMOVAL. To remove a power supply, first use the
POWER switch to turn off the unit. Then loosen the two
mounting screws and extract the unit from the RA 19-1U
Rack Adapter. CAUTION: The ON/OFF switch must be
set to OFF before removing the unit from the rack
adapter.
• Operation in a parallel master/slave configuration
to indicate that a slave unit is no longer within the
proper specifications for paralleled units. Slave 1
should be optimally adjusted to 40mV less than
master, slave 2 adjusted to 40mV less than slave
1, etc. The maximum allowable difference
between paralleled units is 250mv. The minimum
allowable difference between paralleled units is
25mV. If a slave exceeds these limits, the MASTER ON light goes on.
The 3.3V models do not use forced current sharing so the
MASTER ON LED is always off. The MASTER ON LED
for 5V through 48V models goes on under any of the three
following conditions:
POWER
SWITCH
NOTE: MOUNTING SCREW MAX TORQUE: 2 IN.-LBS. (0.23 N x m)
MOUNTING
SCREW
TEST
POINTS
VOLTAGE
ADJUST
TRIMMER
MASTER
ON
LED
MOUNTING
SCREW
• Independent operation.
• Operation in a parallel master/slave configuration
to indicate which unit is the master.
KEPCO, INC. 131-38 SANFORD AVENUE FLUSHING, NY. 11355 U.S.A. TEL (718) 461-7000 FAX (718) 767-1102