Emerson NT5C06D User Manual

Astec Advanced Power Systems

A

UM5C06D ( 169-2071-504 )

Helios Rectifier 25/48 Single Phase -48V, 25 A

Power Factor Corrected Switch Mode Rectifier
NT5C06D

Installation and User Manual

P0831010 Standard 7.00 May 2001

Astec Advanced Power Systems

part of Emerson Network Power

Astec Advanced Power Systems

Helios Rectifier 25/48 Single Phase -48V, 25A

Power Factor Corrected Switch Mode Rectifier
NT5C06D

Installation and User Manual

Manual Number : UM5C06D ( 169-2071-504 )
Manual Status : Standard
Manual Issue : 7.00
Release Date : May 2001
P0831010

Copyright 2001 Astec Advanced Power Systems Ltd
All Rights Reserved

Published in Canada

The information contained in this manual is the property of Astec Advanced Power Systems and is subject to change without
notice. Astec Advanced Power Systems Ltd reserves the right to make changes in design or components as progress in
engineering and manufacturing may warrant. Except as specifically authorized in writing by the V.P. of Engineering and Product
Manufacturing of Astec Advanced Power Systems Ltd, the holder of this manual shall keep all information contained herein
confidential and shall protect same, in whole or in part, from disclosure and dissemination to all third parties, and use the same
for start-up, operation, troubleshooting, and maintenance purposes only. Any modification to the equipment must be approved
by the person responsible for product safety, and design quality at Astec Advanced Power Systems Ltd to ensure that the
equipment complies with the operation standards.

This equipment generates, uses, and can radiate radio frequency energy, and if not installed and used in accordance with the
instructions contained in the Installation and User Manuals, can cause harmful interference to radio communications. Operation
of this equipment in a residential area is likely to cause harmful interference, in which case the user will be required to correct
the interference at his own expense.

Astec Advanced Power Systems
A part of Emerson Network Power

Helios Candeo is a trademark of Astec International Ltd. The Emerson logo is a trademark and service mark of Emerson Electric Co.

Helios Rectifier 25/48NT5C06D Installation and User Manual

Publication history

May 2001

Standard issue 7.00. Manual modified to reflect the Emerson identity.
( EC 102-26438 )

September 1999

Standard 6.0. Document modified to be in accordance with Astec
standards. (ECN 102-17331)

May 1999

Standard 5.0. Document modified to reflect Astec identity. Figure 11
modified. (ECN 102-14852)

March 1997

Std. release 4.0. New Float Voltage and Current Limit Factory
Setting.

August 1996

Std. release 3.0. Removal of extended temperature rectifier models
Table 1 and Table 6 (note) revised.

5

February 1996

Std. release 2.0. This issue is to cover the revision of “Installation and
Start-Up” procedures and Figures 1, 2, 3, 7 and 9

November 1995

Standard release 1.0.

Helios Rectifier 25/48NT5C06D Installation and User Manual

6 Publication history

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UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Contents

Introduction.............................................................................................................. 11

Description....................................................................................................11

Applications .................................................................................................. 12

Equipment Identification.................................................................................. 12

Specifications .......................................................................................................... 15

Electrical specifications................................................................................... 15

Environmental specifications ............................................................................ 17

Installation and start up.......................................................................................... 19

7

MPS75 NT5C10C(X)  power shelf (23-inch) .....................................................12

Helios Rectifier 25/48  NT5C06D(X) –48 V / 25 A Switch Mode Rectifier ........13

Output noise and ripple .........................................................................................16

Efficiency and Power Factor .................................................................................16

Reliability..............................................................................................................16

Heat Dissipation ...................................................................................................16

Electromagnetic interference (EMI) .......................................................................16

Operating..............................................................................................................17

Transportation......................................................................................................17

Storage.................................................................................................................17

Tools and test equipment.................................................................................19

Installing the power shelf................................................................................. 19

Wiring the power shelf..........................................................................................20

Installing the AC power.........................................................................................21

DC Conductors Installation ...................................................................................22

Control and Alarm Connections .............................................................................23

Verification ...........................................................................................................28

Installing the rectifier...................................................................................... 28

Factory setting .....................................................................................................28

Rectifier meter accuracy.......................................................................................29

Start-up and verification .......................................................................................29

Slope Load Share ..................................................................................................32

Helios Rectifier 25/48NT5C06D Installation and User Manual

8 Contents

Forced Load Share ................................................................................................32

Load Share Adjustment Procedure ........................................................................32

Operation.................................................................................................................. 33

Front panel controls........................................................................................ 34

Features ....................................................................................................... 34

Local float / equalize control .................................................................................34

High voltage shutdown (HVSD) - local ...................................................................34

High voltage shutdown - remote............................................................................34

Start-up delay .......................................................................................................35

Test points (V+, V-) ..............................................................................................35

Indicators .............................................................................................................35

Rectifier failure alarm (RFA)..................................................................................35

Fan failure alarm...................................................................................................35

Internal high voltage shutdown (HVSD) .................................................................35

Local ON/OFF control (AC breaker)........................................................................36

Remote ON/OFF control ........................................................................................36

Remote voltage sensing ........................................................................................36

Sense fail alarm (SEN FAIL)...................................................................................36

Current limiting .....................................................................................................36

Soft start / walk-in ...............................................................................................36

AC inrush current..................................................................................................36

Sequential start ....................................................................................................37

Parallel operation ..................................................................................................37

Discharge of output capacitors .............................................................................37

Input AC voltage monitor ......................................................................................38

Thermal shutdown ................................................................................................38

Remote high voltage shutdown .............................................................................38

Local / remote high voltage shutdown reset ..........................................................38

Remote equalize control ........................................................................................38

Power interface edge connector............................................................................38

Signal interface connector ...............................................................................39

Maintenance............................................................................................................. 41

Float / equalize...............................................................................................41

High voltage shutdown (HVSD) ......................................................................... 42

Cooling fan....................................................................................................42

Fan replacement ...................................................................................................43

Power shelf................................................................................................... 45

Troubleshooting ....................................................................................................... 47

Alarm indication............................................................................................. 47

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Contents 9

RFA fault ..............................................................................................................47

SEN FAIL fault ......................................................................................................48

Erratic load fault...................................................................................................48

Current or voltage float fault ................................................................................48

Appendix A: Replacement parts .............................................................................. 49

Appendix B: Technical service assistance ............................................................. 51

Local toll-free prefixes .................................................................................................51

Toll-free technical assistance numbers.........................................................................52

List of terms and acronyms..................................................................................... 53

List of Figures

Figure 1 - MPS75 Modular Power Shelf-NT5C10C with 8-pin signal cables .................13

Figure 2 - MPS75 Modular Power shelf- NT5C10C with 26-pin signal connectors........14

Figure 3 - NT5C06D Switch Mode Rectifier .................................................................14

Figure 4 - Power shelf common AC connection.............................................................21

Figure 5 - Power shelf individual AC connection...........................................................22

Figure 6 - Connecting the DC power shelf ....................................................................23

Figure 7 - No controller, remote sensing connection for 8-pin signal cable shelves........26

Figure 8 - No controller, remote sensing connection for a 26-pin signal connector

shelf...........................................................................................................27

Figure 9 - NT5C06D - front view..................................................................................34

Figure 10 - Power interface connections ......................................................................39

Figure 11 - Control signal connections .........................................................................40

Figure 12 - NT5C06D rear view ...................................................................................44

List of Tables

Table 1 - Electrical specifications.................................................................................15

Table 2 - AC cable wire size.........................................................................................21

Table 3 - AC Fuses.......................................................................................................21

Table 4 - DC cable wire size.........................................................................................23

Table 5 - Rectifier and Controller interface connections (8-pin connectors) ..................24

Table 6 - Rectifier and Controller interface connections (26-pin connector)..................24

Table 7 - Rectifier settings ..........................................................................................28

Table 8 - Indicators......................................................................................................35

Table 9 - System fault diagnosis..................................................................................47

List of Procedures

Procedure 1 - Installing the power shelf .......................................................................20

Procedure 2 - Verification ............................................................................................28

Procedure 3 - Rectifier installation procedure...............................................................28

Procedure 4 - Starting up the rectifier..........................................................................29

Procedure 5 - Adjusting the load share.........................................................................32

Procedure 6 - Adjusting the float / equalize ..................................................................41

Procedure 7 - Replacing the fan ...................................................................................43

Helios Rectifier 25/48 Installation and User Manual

10 Contents

This page is left blank intentionally.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

1. Introduction

Description

The NT5C06D Switch Mode Rectifier is rated for 25 A at -48 V DC. This
rectifier incorporates AC input power factor correction circuitry, is highly
efficient and lightweight (15 lbs.). It is fully connectorized and plugs into a
power shelf into which up to three rectifiers can be installed. The rectifier is
forced air cooled with air entering from the front and exhausting out the rear
of the power shelf.

Separate or common AC power feeds are connected to the power shelf to
provide power to each rectifier through the back plane connectors. The
rectifier requires a single phase AC source at a nominal voltage of 208/240 V
AC, 50 or 60 Hz. The AC power can be supplied from a single phase source
or a three-phase system connected phase to phase. The rectifier can also be
powered from a 380 V AC WYE system connected phase to neutral (that is,
220 V phase-neutral).

The negative and positive outputs of each rectifier are connected to two
common busses (BAT -48 and BAT RTN +). The power shelf is designed
for a typical capacity of 75 A. The design of the rectifiers allows rectifiers
located in the same power shelf, or other shelves, which are connected in
parallel, to share the load, either by forced load share or by an output
negative slope method.

11

The back plane of the power shelf is equipped with two types of signal
connectors. One is an eight-pin (male) connector that provides the interface
to analog type controllers. The other connector is a twenty-six-pin flat cable
(female) type connector compatible with the Helios system family and
provides a larger diagnostic capability.

Each rectifier provides a variety of monitoring and alarm features such as,
rectifier failure alarm, fan fail alarm, ac fail alarm, remote sensing, sense fail
alarm, local and remote high voltage shutdown, automatic high voltage
shutdown reset, temporary release, remote and local equalize, and remote
shunt monitoring.

Helios Rectifier 25/48NT5C06D Installation and User Manual

12 Introduction

Applications

The rectifier is designed to function as the prime source of power for
equipment requiring -48 V DC. It will also operate as a battery charger or as
a battery replacement (batteryless operation). Its low output noise and good
voltage regulation, combined with a 0.01% V coefficient for each degree C of
temperature, provides an excellent charging facility to maintain a battery fully
charged.

The NT5C06D rectifier is designed to operate continuously in a small or
large power system. The NT5C06D is compatible with all other Astec
rectifiers, and can be interfaced with other commercially available standard
(compatible) rectifiers and power plants. The NT5C06DA/DB is designed to
operate in temperatures ranging from 0°C to 65°C.

Equipment Identification

This section contains a description of the major components and available
options for the NT5C06D Rectifier, and the MPS75 power shelves.

NT5C06DA -48 V / 25 A Switch Mode Rectifier, brown

NT5C06DB -48 V / 25 A Switch Mode Rectifier, dolphin grey

NT5C10C(X) Rack mount power shelf family, 23” mounting

Note: Many shelf models, with different colors and features, are

available.

MPS75 NT5C10C(X)  power shelf (23-inch)

The MPS75 is a power shelf that can support up to three NT5C06 rectifiers.
The rectifiers plug into the shelf, which provides interconnection points for
AC input, DC output, and alarm and control signals. Each power shelf
requires either three AC feeds (one for each rectifier) for the individual AC
models, or a single AC feed for the three shelf rectifiers for the common AC
models. Its output connects to the charge busbar or to the load distribution

panel through two cablesbattery and battery return. Each rectifier position
has its own connector-terminated alarm and control cable going to the power
plant control and monitor unit.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Introduction 13

Helios Rectifier 25/48  NT5C06D(X) –48 V / 25 A Switch Mode Rectifier

The NT5C06D provides -48 V / 25 A of isolated, filtered, and regulated DC
power from a single phase AC source, for powering a load while charging a
positive grounded battery. The output voltage can be adjusted from 46.0 to

56.0 V for floating a 23 or 24 cell battery string.

The rectifier is designed for automatic precharge upon insertion into the
MPS75 power shelf. When the NT5C06D is plugged into a power shelf with
battery back-up, or with other rectifiers running, the DC circuit breaker must
be in the OPEN position (OFF position).

Each rectifier plugs into the MPS75 power shelf and does not require any
other connections. The rectifier is equipped with a 13 A, two-pole, AC input
circuit breaker; a 35 A, single-pole, DC output circuit breaker; a digital
ammeter; and a set of LEDs, switches and potentiometers for threshold
adjustments and alarm indication. The rectifier uses high frequency switching
technology, is cooled by forced air, and can be equipped with an optional air
filter.

Figure 1 - -MPS75 Modular Power Shelf-NT5C10C with 8-pin signal cables

AC
Connections

Height: 178 mm (7.0 inches)

Depth: 305 mm (12.0 inches)
Width: 533 mm (21.0 inches)

Weight: 10.5 kg (23.0 lbs)

DC Connections

Signal Cables
to Controller

Helios Rectifier 25/48 Installation and User Manual

14 Introduction

Figure 2 - MPS75 Modular Power shelf- NT5C10C with 26-pin signal connectors

Mounting
holes (4)

Signal cable connection

Figure 3 - NT5C06D Switch Mode Rectifier

Height: 168 mm (6.60 inches)
Depth: 260 mm (10.25 inches)
Width: 149 mm (5.85 inches)
Weight:6.8 kg (15 lbs)

EQL

FLT

FAN
HVSD

ON RFA

Mounting
holes (4)

DC connection

DC

CC

AC

OUTPUT

V+

V-

SO RTIE

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

CA

F1

3MA 250V

LOA D
CHARG E

MPR25
MPR15

2. Specifications

Electrical specifications

The NT5C06D rectifier operates within the electrical specifications listed in
Table 1. (Refer to the Product Specification which can be obtained from the
Engineering department of Astec Advanced Power Systems).

Table 1 - Electrical specifications

15

Input Voltage Rating:

Input Current Rating:

Recommended AC Service
Input Fusing:

Output Voltage Rating:

Output Current Rating:

Input Protection:

Nominal 208 / 240 V AC single-phase, 47-63 Hz.
Input Voltage Range 176 to 264 V AC.

Starting range 184 to 260 V AC.

When three-phase 208 / 240 V AC source is available to power the
MPS75, it is preferable to distribute the rectifiers among the phases.

7.5 A nominal at 208 V AC input and -56 V DC, 25 A output. Use RW­90 wire (or equivalent) as listed in Table 2.

Two slow flow fusePRN type or equivalent, one for each AC line
input; or one slow trip circuit breaker for each rectifier, as listed in
Table 3.

Float: -46 V DC to -56 V DC
Equalize: 0 - 4 V DC over float. Maximum -59.5 V DC.

25 A for each rectifier.

Two-pole 13 A circuit breaker, opens both lines for 208 / 240 V AC
service.

continued

Helios Rectifier 25/48NT5C06D Installation and User Manual

16 Specifications

Table 1 - Electrical specifications ( continued )

Output Protection:

Output Regulation:

Output noise and ripple

Less than 22 dBrnC at voice frequency (with or without batteries and
measured at the point of regulation) from a 1 A load current to full load,
including the current limit mode. Less than 32 dBrnC for loads less than 1 A.

Less than 10 mVrms in any 3 kHz band between 10 kHz and 20 MHz.
Measurements are made with batteries at the output terminals of the power
shelf and with the rectifier in the local sensing mode.

Less than 250 mV peak to peak switching voltage spikes measured
differentially by an oscilloscope with a 100 MHz bandwidth.

A single pole 35 A circuit breaker is connected in series with the
negative output lead of the rectifier.
The rectifier contains an adjustable output current limit circuit for
protection against damage from overloads. This circuit is factory set to
limit the output current to 30 A. It can, however, be adjusted from

12.5 A to 30 A.

At point of regulation: within ± 0.5% of the selected value for all
specified input and output variations and within ± 1% for any
combination of specified input, output, and environmental conditions.

Efficiency and Power Factor

Efficiency is better than 90% at a nominal input voltage of 240 V AC, -54 V
DC and an output load greater than 15 A.

The power factor is 0.98 at loads greater than 10 A and 0.99 for loads greater
then 20 A.

Reliability

The rectifier has a predicted mean time before failures (MTBF) greater than
120,000 hours under normal operating conditions at 30°C.

Heat Dissipation

The maximum heat dissipation is 156 W or 8.87 BTU’s / minute at -56 V /
25 A.

Electromagnetic interference (EMI)

The rectifier meets the EN50081-1 (CISPR22 and EN55022) class "B"
requirements for conducted and radiated EMI.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Environmental specifications

Operating

The rectifier will operate satisfactorily under the following environmental
conditions:

Temperature Range: 0° to +65° C (32° to 149° F)

NT5C06DA/DB equipped without an air filter

0° to +50° C (32° to 122° F)

equipped with an air filter

Specifications 17

CAUTION

An airflow clearance must be left at the rear of the shelf.
A minimum of three inches is recommended.

Humidity: 0 to 95% RH (non-condensing)

Altitude: Sea level to 2100 m (7000 ft.)

Transportation

During transportation the rectifier can be subjected to the following
conditions without sustaining damage:

Temperature Range: -55° C (-67° F) for 16 hours

+70° C (158° F) dry heat

Humidity: 0 to 95% (non-condensing) 4 kPa max.

Vibration: 38mm/sec max. (10 to 30 Hz).

610 mm (24 inch) drop when packaged.

Pressure: 12 kPa min. (equiv. to 15 000 m altitude).

Temp. Shock: -55° to 70°C (-67° to 158°F) (5 cycles)

Storage

For storage, the rectifier must not be kept in an environment exceeding:

Temperature Range: -55°C (-67°F) +70°C (158°F) dry heat

Humidity: 0 to 95% (non-condensing) 4 kPa max.

Helios Rectifier 25/48 Installation and User Manual

18 Specifications

The rectifier contains aluminum electrolytic capacitors having a shelf life of 5
years or greater when stored at the maximum rated storage temperature.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

3. Installation and start up

The power shelf must be installed on the framework and all AC, DC and
control and alarm wiring must be connected before the rectifiers are
physically plugged in.

Tools and test equipment

The following tools and test equipment are required:

• Screwdriver, flat blade (3/8-inch)

• Screwdriver, flat blade (3/32-inch)

• Screwdriver, Burns No. 60, or equivalent

• Cable strippers / electrician’s knife

• Wire stripper

• Cable cutters (2/0)

• Linesman’s pliers

• Open and box ended wrenches (set)

19

• Socket set (1/2-inch drive)

• Ratchet Wrench (1/2-inch drive)

• Torque limiting torque wrench (1/2-inch drive)

• Crimper, T & B 12 or 15 Ton head with 94H die

• Digital Multimeter, Fluke 8000A or equivalent

Installing the power shelf

Installation of the power shelf consists of mounting the shelf in a cabinet or
relay rack and connecting the AC, DC, and control and alarm connection
cables.

Helios Rectifier 25/48NT5C06D Installation and User Manual

20 Installation and start-up

Procedure 1 - Installing the power shelf

Step Action

1 Position the power shelf, without any rectifiers plugged in, against the

framework.

2 Secure the shelf in the position indicated by the job drawing (normally directly

below the controller or another shelf). At least one star washer must be
installed on one holding screw to ensure maximum framework ground
continuity.

3 Release the clamping bar from the front of the power shelf

4 Remove the AC and DC junction box cover, located on the left and right sides.

Store the parts for reinstallation after the wire connections have been
completed.

Wiring the power shelf

Once the power shelf has been installed and firmly secured proceed with the
wiring.

end

CAUTION

The power shelf wiring should be installed by qualified
personnel and in accordance with the local electrical codes.

DANGER

Input voltage to the rectifier and the power shelf is at a
hazardous potential. Ensure that the power switch is OFF
at the AC service panel working on the power shelf.
Hazardous voltages may still be present at the terminals
even if the rectifiers are OFF. Use a voltmeter to verify the
absence of voltage.

DANGER

Improper wiring can cause personal injury and equipment
damage. Verify the proper polarity of the battery leads
before connecting them to the power shelf, and clearly
identify the positive and negative leads.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Installing the AC power

Permanent AC connection to the MPS75 power shelf is done using two
armored cable conductors, RW-90 or equivalent, as listed in Table 2. One
must be routed to L1, and the other one to L2 and to the safety shelf frame
ground (FR GND). The cabling must comply to the local electrical code. The
power shelf is equipped with a strain relief to terminate the conduit. The
cable length should be minimized and be properly secured.

Table 2 - AC cable wire size

2 RECTIFIER POSITIONS 3 RECTIFIER POSITIONS

Individual AC 12 AWG for each rectifier 12 AWG for each rectifier.

Common AC 8 AWG 6 AWG

Table 3 - AC Fuses

2 RECTIFIER POSITIONS 3 RECTIFIER POSITIONS

Individual AC 20 A max for each rectifier 20 A max for each rectifier

Common AC 40 A max. 60 A max.

Installation and start-up 21

Figure 4 - Power shelf common AC connection

FR GRD

L2

L1

Helios Rectifier 25/48 Installation and User Manual

22 Installation and start-up

Figure 5 - Power shelf individual AC connection

POS 3 POS 2 POS 1

L1 L2 L1 L2 L1 L2

FR GRD

654 321

When cabling the AC to the power shelf, make sure that each corresponding
safety ground wire is properly connected to the terminal designated FR
GND.

This grounding is proven to be sufficient, but for systems requiring an extra
ground connection, an 8 AWG cable wire (color green, insulation 105°C) can
be installed in addition to the existing cable and be connected to an external
system ground. The new ground wire can be installed on one of the existing
FR GND terminal screws located inside the power shelf with a 0.25-inch
terminating ring lug. The wire must be routed along the top back of the shelf
and come out the back opening on the right DC cabling side. Make sure that
the wire does not interfere with the rectifier connections.

CAUTION

Do not insert fuses or operate circuit breakers (switches)
until the entire system has been assembled and you have
been instructed to do so in the appropriate procedure.

DC Conductors Installation

Make the connections at the power shelf prior to connecting DC leads to the
battery or the distribution (load). Permanently connect the shelf to the
interconnect and distribution panel using the properly-size cable by referring
to Table 4. The DC output of the rectifiers is terminated on two busbars
(RTN & -48 V) located on the right side of the shelf. The length of the
conductors should be minimized to reduce voltage drops and interference.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Table 4 - DC cable wire size

1 RECT. POSITION 2 RECT. POSITIONS 3 RECT. POSITIONS

8 AWG 6 AWG 4 AWG

Figure 6 - Connecting the DC power shelf

Installation and start-up 23

Control and Alarm Connections

The rectifier is interfaced to the power plant controller through the signal
connectors provided on the backplane of the power shelf (see Figures 1 and
2 for location). These signal connectors provide control, alarm, and
monitoring signals.

The power shelf provides two types of signal connectors. One ribbon cable
26-pin female connector, or multiple eight-pin male cable connectors are
used to interface the rectifiers to the power plant controller and monitoring
unit. The control inputs are activated by a BAT RTN signal. The alarm
signals extended by relay contacts are isolated from each other and from the
chassis. All contacts are rated 60 V DC and 0.5 A.

Helios Rectifier 25/48 Installation and User Manual

24 Installation and start-up

Table 5 - Rectifier and Controller interface connections (8-pin connectors)

Pin # Design. Description Signal

1 EQL Remote Equalize BAT RTN
2 RG+ Sensing Positive BAT RTN
3 RC- Sensing Negative -48V
4 FAN ALM Fan Failure BAT RTN
5 HVSDR Remote High Voltage Shutdown Reset BAT RTN
6 HVSD Remote High Voltage Shutdown BAT RTN
7 RFA Rectifier Failure Alarm BAT RTN
8 TB Temporary Release BAT RTN

Note:

Both RFA and Fan alarm relays are energized during

normal operation and are de-energized during an alarm
condition.

Table 6 - Rectifier and Controller interface connections (26-pin connector)

Pin # Designation Description Signal

1 RC1 - Sensing Negative rect (1) BAT­2 RFA1 (NC) Rectifier (1) fail alarm NC
3 TR1 Temporary Release Rect (1) Bat RTN
4 SH1+ Shunt Positive Rect (1) 50 mV
5 SH1- Shunt Negative Rect (1) 50 mV
6 RC2- Sensing Negative Rect (2) BAT­7 RFA2 (NC) Rectifier (2) fail alarm NC
8 TR2 Temporary Release Rect (2) Bat RTN

9 SH2+ Shunt Positive Rect (2) 50 mV
10 SH3- Shunt Negative Rect (3) 50 mV
11 RC3- Sensing Negative Rect (3) BAT­12 RFA3 (NC) Rectifier (3) fail alarm NC
13 TR3 Temporary Release Rect (3) Bat RTN
14 SH3+ Shunt Positive Rect (3) 50 mV
15 SH3- Shunt Negative Rect (3) 50 mV
16 CUR SHARE Current Share 0 - 12VDC
17 RFA (C) Rectifier Fail Alarm Common
18 ALM COMMON Alarms Common Common
19 EQL Remote Equalize BAT RTN
20 RG+ Sensing Positive BAT RTN
21 HVSDR Remote High Voltage Shutdown Reset BAT RTN
22 HVSD Remote High Voltage Shutdown BAT RTN

continued

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Installation and start-up 25

Table 6 - Rectifier and Controller interface connections (26-pin connector) ( continued )

Pin # Designation Description Signal

23 DC BRK ALM DC Circuit Breaker NC
24 AC FAIL ALM AC Line Fail Alarm NC
25 SENSE FAIL

Sense Fail NC

ALM

26 FAN ALM Fan Alarm NC

Note:

The normally closeed (NC) annotation signifies that the
alarm is sent when the contact between the alarm (NC)
and alarm common is closed (short-circuited). The alarm
RFA (C) and alarm common pins 17 and 18 are floating.
These two alarm commons must be connected to the bat
RTN at the system level for applications requiring non­floating alarm signals. The rect (1) indicates the rectifier in
position (1) located on the right side of the MPS75 shelf.

In applications where no controller is available or desired, the current sharing
functions among rectifiers in SLOPE or FORCE mode are still available.
The signal cable remote sense connections RC- and RG+ must be connected
to the desired remote sensing location ( batteries). In forced share mode, the
forced share signal line of each shelf must be connected together in a daisy
chain fashion. See Figures 7A and 7B for suggested methods of connecting
the signal wire.

Helios Rectifier 25/48 Installation and User Manual

26 Installation and start-up

Figure 7 - No controller, remote sensing connection for 8-pin signal cable shelves

Note 1:

Note 2:

Note 3:

Note 4:

Refer to MS5C06 for available 8-pin ribbon signal cables
of different lengths to connect from the shelf back plane
rectifier position to the remote sensing point.

Identify the wire color corresponding to RG+ pin 2 and
RC- pin 3 to be used for the remote sensing. Completely
cut out completely the 8-pin connector, leaving the signal
wires loose. Insulate each unused wire with electrical tape.
Use the pin references to identify the signals as described
above.

Use #20 AWG (105°C) wire.

Use 1.6A fuse A0384386 with ferrule type fuse holder

A0384387.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Installation and start-up 27

Y

Figure 8 - No controller, remote sensing connection for a 26-pin signal connector shelf

20 AWG (SEE NOTE 3)

SEE NOTE 4

RC-

RC FUSE 1.6 AMP

RG+

+

-

BATTER

(PIN 16)

26 pins ribbon

conne ctor mate

16

1611 20

16

or desired regulation point

Printed circuit or

wire wrap board

(Seenote 2)

Force sha re line

Shelves interconnect

points

SIGNAL CABLES FROM SHELVES

(

see note 1 )

Note 1:

Refer to MS5C06 for available signal cables of different

lengths, to connect from the shelf backplane rectifier
position to the remote sensing point.

Note 2:

Use a printed circuit or wire-wrap board to interface all

the 26-pin connector ribbons from all the shelves. All
RC- signal connections (pin 11, 6, 1) must be joined
together. All the RC+ connections (pin 20) must also be
joined together. For forced share current mode
applications, the force share signal (pin 16) must also be
interconnected between the shelves.

Note 3:

Note 4:

Use #20 AWG (105°C) wire.

Use 1.6A fuse A0384386 with ferrule type fuse

holder A0384387.

Helios Rectifier 25/48 Installation and User Manual

28 Installation and start-up

Verification

After completing the wiring of the power shelf perform the following:

Procedure 2 - Verification

Step Action

1 Verify that the power shelf has been mechanically secured.
2 Verify that all the wiring performed is correct by using a voltmeter.
3 Verify that all connections are mechanically correct (that is, tight, correct

4 Reinstall the AC and DC junction box cover on the left and right sides.

Installing the rectifier

The NT5C06D rectifier is a plug-in unit intended for use in the MPS75
power shelf.

Procedure 3 - Rectifier installation procedure

connector, correct marking etc.)

end -

Factory setting

The rectifier is factory set as indicated in Table 7.

Table 7 - Rectifier settings

Step Action

1 Release the clamping bar by loosening the two captive screws
2 Remove the blank panel for the rectifier to be installed (place a finger in the

hole, lift up, pull forward, then lower to disengage upper tabs from the shelf
top). Store the panel at the bottom of the shelf, under the rectifier.

3 Ensure that both AC and DC circuit breakers are in the OFF position.
4 Use a voltmeter to verify that the AC supply at the input of the shelf is 208

/ 240 V AC nominal.

5 Carefully slide the rectifier in position on top of the stored blank panel.
6 Insure that the rectifier is firmly slid and seated into position.
7 Reinstall the clamping bar by securing the two captive screws.

end

Load

Slope load sharing method

Sharing

Rectifier Output Voltage (FLOAT) 54.5 V DC ± 0.1 V
Rectifier Output Voltage (EQUALIZE) 55.2 V DC ± 0.1 V
Rectifier High Voltage Shutdown (HVSD) 59.0 V DC ± 0.1 V
Rectifier Output Current Limit 30 A ± 0.5 A

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Rectifier meter accuracy

The rectifier's current meter is precise within + 2%.

Start-up and verification

Repeat the following steps for each rectifier in turn.

Procedure 4 - Starting up the rectifier

Step Action

1 Close the AC circuit breaker in the AC service (main) panel.
2 Connect an external meter to test points V- and V+ on the rectifier to be

tested.

3 Switch the AC circuit breaker of the rectifier. The voltmeter will indicate a

float voltage.
Note: If the float voltage remains at 0 V DC, verify that the input voltage is

4 Determine the system requirements for Float, Equalize and HVSD limits

found in User Manual 167-7011-010. If the rectifier's factory set limits
have to be changed, proceed as follows, otherwise proceed to step 13.

High Voltage Shutdown ( HVSD ) Adjustment :

5 With the DC circuit breaker OFF, keep the AC breaker on and turn the HVSD

potentiometer fully clockwise.

6 Turn the FLT potentiometer slowly clockwise until the output voltage

reaches the desired HVSD set point.

7 Slowly turn the HVSD potentiometer counterclockwise until the rectifier

shuts down and the float voltage starts to decay down to zero. Turn the
Float potentiometer counterclockwise two turns and reset the rectifier by
switching the AC circuit breaker OFF and then ON.

8 Adjust the Float voltage to the correct level.

Float Voltage Adjustment :

9 To adjust the float voltage use the FLT potentiometer. To increase the

voltage turn the potentiometer clockwise, to decrease it turn it
counterclockwise .

Installation and start-up 29

within the specified range. If it stills remains at 0 V DC, refer to the
troubleshooting section of this manual.

continued

Helios Rectifier 25/48 Installation and User Manual

30 Installation and start-up

Procedure 4 - Starting up the rectifier ( continued )

Step Action

10 In order to accurately adjust the rectifiers float and/or equalize (if different

from factory setting) the current share mode setting must be taken into
account.
Two modes of share are offered in the NT5C06DA/DB.

(i) Slope Share
The output voltage linearly decreases by -300mV from 0-100% of output
current capacity (0-25 A). Therefore to accurately PRESET the rectifier's
float voltage, it's running current within the plant environment must be
predicted and the output voltage modified according to expression below:

V.(preset) = Vo (desired) + (Io (running)

x .3v)
25
or
% Io (running) x .3v
For example: if the rectifier is expected to provide 12.5 A at 52.2 V then:

Vo(preset) = 52.2 + (12.5 x .3 V)
25
= 52.2 + .15 V
= 52.35 V
In Slope Share mode the rectifier's output may need to be corrected slightly
in order for it to share equally with any other rectifiers.

The SLS/FS switch of the rectifier (and all other rectifiers in parallel with it)
must be pushed toward SLS for slope mode sharing.

continued

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Installation and start-up 31

Procedure 4 - Starting up the rectifier ( continued )

Step Action

11 (ii) Forced Share

In the forced share mode, the rectifier's output voltage setting is not
modified with changes in output load as is the case in the Slope Share
mode. The preset output voltage is the value the rectifier will operate at
throughout its load range*.
Adjust the rectifier float voltage to the desired system float voltage.

Once the rectifier's output voltage has been preset with the DC breaker
OFF, turn the DC breaker ON and the rectifier is now connected in the
system.

In forced share mode, current sharing will be automatic providing the
rectifiers' outputs are preset within 0.5 V of each other.

• less than 0.1 V from no load to full load, that is:

~ 0.2%.

12 Equalize Voltage Adjustment (EQL)

Maintain the FLOAT/EQL switch to the EQL position. Turn the EQL
potentiometer clockwise to increase the voltage or counterclockwise to
decrease it. Use the same consideration as in "Float Adjustment" for
determining the desired EQL setting.

13 Current Limit Verification (CL)

The current limit is factory set to 30 A. The CL ADJ potentiometer can be
set within the range of 12.5 to 30 A. Verification or adjustment of the CL
setting point requires an external load or the office load can be used.
Switch OFF or adjust other rectifiers to a lower voltage, thus forcing the
rectifier under test to pickup more load. When the rectifier reaches its
current limit point, the current indication will remain constant and the float
voltage will start to drop.

14 Load Sharing

Two Load Sharing methods are available:

- Slope load sharing

- Forced load sharing (positive bus).
The load sharing method can be selected with the SLS / FS switch located
on the front panel of the rectifier.
For more information about these two methods, see the 'Parallel Operation'
Section of this manual.
Go to procedure N 5 for the load share adjustment procedure.

end

Helios Rectifier 25/48 Installation and User Manual

32 Installation and start-up

Slope Load Share

When the rectifier is connected in parallel with rectifiers in the same power
shelf, or other power shelves, and this method of load sharing is desired, the
SLS / FS switch of each rectifier must be pushed towards the SLS.

Forced Load Share

When the preferred method for load sharing is Forced Load Share, the SLS /
FS switch of each rectifier must be pushed toward the FS designation. The
power shelf must be connected to the next shelf through the 26-pin ribbon
signal connector (pin-16), or to other compatible rectifiers equipped with a
forced load share signal 0-12 volt positive bus.

Load Share Adjustment Procedure

If, after presetting the output voltage (float or equalize), the rectifier does not
share the load with the other rectifiers in the power plant, take the following
steps:

Procedure 5 - Adjusting the load share

Step Action

1 Verify that all the share mode settings are the same SLS or FS.
2 Verify that all the rectifier sense points are the same.
3 Verify that all the rectifiers are in float or all are in the equalize mode (that

is, the modes are not mixed).

4 If the above three cases are true, then this output voltage is

maladjusted.
Follow step A or B below.

A) If the rectifier is in Slope Share:

With the DC breaker ON, adjust the FLT (or EQL) potentiometer
clockwise, if the current is too low, or counter clockwise, if the
current is too high.

B) If the rectifier is in Forced Share:

Rectifier output is maladjusted by more than + 0.5 V. OPEN the DC breaker
and adjust the rectifier output within 0.1 V of the plant voltage. Adjust the
rectifier float voltage to the desired system float voltage. CLOSE the DC
breaker and the rectifier will automatically share the load.

end

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

4. Operation

In addition to rectifying the AC, the input circuit provides EMI filtering,
inrush current limiting, low and high AC inhibit, power factor compensation,
surge voltage protection, and is equipped with a 13 A AC breaker for input
protection.

The output section provides additional EMI filtering and contains an internal
shunt for output DC current measurement and a 35 A circuit breaker for
output protection.

The monitoring circuitry includes; soft start, rectifier fail alarm (RFA),
monitoring and control for local and remote equalize, temporary release,
thermal shutdown, low and high AC voltage inhibit, loss of AC voltage
alarm, local and remote high voltage shutdown (HVSD), local and remote
HVSD reset, and fan failure detection.

A 2-1/2 digit output current meter displays the output current. An internal
logic power supply provides the various voltages required by the logic
circuitry and the cooling fan unit.

33

Helios Rectifier 25/48NT5C06D Installation and User Manual

34 Operation

Front panel controls

Figure 9 - NT5C06D - front view

Features

In addition to the features and performance characteristics described earlier,
the rectifier provides the following features.

Local float / equalize control

The rectifier is equipped with a float / equalize switch. The rectifier normally
delivers a float voltage set by the FLT potentiometer. When the switch is
placed in the EQL position, the rectifier changes to equalize mode and
boosts the output voltage to the value set by the EQL potentiometer.

High voltage shutdown (HVSD) - local

This potentiometer sets the internal threshold level for the local high voltage
shutdown monitor circuit.

High voltage shutdown - remote

The rectifier can be shut down by an external (remote) HVSD signal from
the controller only if it is delivering more than 3 A +/- 0.75 A.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Start-up delay

This unit does not have a start-up delay.

Test points (V+, V-)

Test points allow the user to measure the voltage at the point of regulation.
A 100 ohm PTC resistor is placed in series with both leads to prevent
damage caused by short circuits at the jack terminals.

Indicators

Table 8 - Indicators

Operation 35

LAMP

DESIGNATION

RFA Red/Green Rectifier Fail Alarm / normal operation
FAN ALM Red Fan Fail Alarm

Rectifier failure alarm (RFA)

The rectifier incorporates facilities for monitoring its operational status and
extends a global alarm upon detection of an internal failure. An abnormal or
out of range AC input voltage, an internal fuse failure, any circuit breaker
opening, any system or internal shutdown (for example: Thermal or HVSD),
or any internal failure causing a disappearance of power switching, will trigger
the RFA alarm and light up the RFA LED (color red) located on the front
panel. If the disappearance of switching, however, is caused by an incorrect
adjustment of the output FLT voltage, resulting in no output load, the RFA
will not be triggered since no real failure will have occurred.

Fan failure alarm

Loss of all or part of the cooling system activates the FAN ALM and lights
up the appropriate LED on the front panel. An RFA will be triggered, the
rectifier will be inhibited and both a FAN ALM and RFA will be generated.

COLOR DESCRIPTION

The defective fan cooling fan unit can be ordered and replaced by the
customer.

Internal high voltage shutdown (HVSD)

The rectifier is equipped with a high voltage monitor. Whenever the rectifier
output voltage exceeds a preset value adjustable from -52 V to -59.5 V, the
rectifier shuts down. The rectifier will attempt to restart itself automatically
after an HVSD. However, if another HVSD occurs within approximately 5
minutes, the rectifier will shut down, lock out and transmit an RFA. This
function is independent of the output load condition. The AC breaker must
be toggled to reset the unit.

Helios Rectifier 25/48 Installation and User Manual

36 Operation

Local ON/OFF control (AC breaker)

The AC input circuit breaker can be used to locally turn the rectifier
ON/OFF. The local ON/OFF control overrides remote control signals.

Remote ON/OFF control

When a battery return (BAT RTN) signal is applied to the 'Temporary
Release' (TR) input, the rectifier inhibits its operation ( no RFA will be
transmitted). Upon removal of the remote ground signal the rectifier returns
to normal operation.

Remote voltage sensing

Provision is made to extend the sensing leads to the battery or to the
charge / discharge bus (batteryless operation) of the plant. Opening either
sense lead will not adversely affect the rectifier output voltage and the
rectifier will default to internal sensing mode.

Sense fail alarm (SEN FAIL)

In the event that the remote sense leads are not connected or reversed, the
RC fuse on the controller fails, or the DC circuit breaker is opened. An alarm
will be transmitted through the signal connector only.

Current limiting

The rectifier will limit the output current to 30 A + 0.5 A (factory setting).
The current limit level can be adjusted between 12.5 A to 30 A at 54.5 V DC,
or to any combination limited to 1635 W of output power within the
adjustable voltage range. Extended periods of operation in the current
limiting mode and repeated transitions between constant-voltage operation
and constant-current operation will have no detrimental effect on the
rectifier’s performance, or service life.

The rectifier is capable of starting when connected across a completely
discharged battery without requiring human intervention or operation of
protection devices. Transitions from constant-voltage operation to constant­current operation and constant-current operation to constant-voltage
operation will occur automatically as determined by the output current. The
current limit circuit will remain working in both the float and equalize modes.

Soft start / walk-in

The rectifier incorporates a walk-in circuit that limits the output current rise
to about 3 A +/- 0.5A every second.

AC inrush current

The AC current during the turn-on sequence of the rectifier, under all input
and output conditions specified in this document, will not exceed its full load
steady-state value.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Sequential start

The rectifier TR lead is available for use with an external sequential start circuit.

Parallel operation

The rectifier is capable of operating in parallel with other rectifiers having similar
output characteristics and shares the total load proportionally to its output rating.

Two load-sharing methods are available:

- Slope load sharing

- Forced load sharing (positive bus)

The load sharing method is normally set at the time of installation by the SLS / FS
switches located on the front panel of the rectifier. The rectifier is factory set to the
Slope Load Sharing Mode.

a) Slope Load Sharing (SLS)

When the SLS / FS switch is set to the SLS position, load sharing is

Operation 37

achieved, by a -300 mV slope on the output voltage, from no load to
full load on the rectifier. This mode should be used when rectifiers
from different vendors are used which are not all equipped with the
forced load-sharing feature. In this mode the units will share the load
within +

10% of their maximum output rating.

b) Forced Load Sharing (FS)

When the SLS / FS switch is set to the FS position, forced load

sharing is achieved by an internal control circuit which, by slightly
modifying the loop reference, achieves equal output current between
rectifiers. For this to occur the rectifiers must communicate their
operating current to other units on the same power plant. The CS
terminals of the rectifiers in the same power shelf are connected
through the back plane (for shelves equipped with a pcb backplane
only). In this mode the units will share the load within +
maximum output rating.

Discharge of output capacitors

The output capacitors will be completely discharged (< 2 V) two minutes
after the AC power has been removed and the rectifier has been
disconnected from the batteries or parallel units.

2% of their

Helios Rectifier 25/48 Installation and User Manual

38 Operation

Input AC voltage monitor

The rectifier monitors the input voltage, inhibits its operation and sends an
RFA when the AC voltage decreases below 176 or rises above 264 V AC. An
AC FAIL alarm contact is transmitted through the signal connector.

The rectifier recovers its normal operation automatically when the input
voltage returns within the acceptable limits, without any operator
intervention.

Thermal shutdown

The rectifier protects itself against thermal over stress by inhibiting its
operation for the duration of the high temperature condition. The RFA
alarm is triggered.

Remote high voltage shutdown

In addition to the local high voltage shutdown feature, the power plant
controller can shut down any rectifier by sending a high voltage shutdown
signal, ground (BAT RTN) pulse. The rectifier will shut down within 50 ms if
it is supplying more than 3 A +/- 0.75 A.

Local / remote high voltage shutdown reset

The rectifier may be reset from an HVSD condition either by toggling the
rectifier’s AC circuit breaker, or by applying a ground signal at the HVSDR
input of the rectifier, provided that the 'TR' lead is not activated.

If the HVSD condition subsides the rectifier will restart automatically. If a
second HVSD event occurs within a 5-minute interval the rectifier will lock
out on the second event and have to be manually or remotely reset to restart.

Remote equalize control

The rectifier is equipped with remote equalize control. This control is
operated by applying a remote ground signal (BAT RTN) and returns to
normal (Float) operation upon removal of the signal.

Power interface edge connector

The rectifier AC, DC, and chassis ground interface is done through the
power interface edge connector. This connector is designed to establish the
frame ground connection first. Figure 10 shows the rectifier to shelf power
interface connections.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Figure 10 - Power interface connections

Operation 39

Signal interface connector

Figure 11 shows the pin assignment of the signal interface connector. This
connector is used to interface all the control, alarm and monitoring signals
with the power shelf that, in turn, interfaces these with the Controller. The
control inputs are activated by a ground (BAT RTN) signal. The alarms are
extended by relay contacts and are isolated from each other and from the
chassis. All contacts are rated 60 V DC and 0.5 A.

Helios Rectifier 25/48 Installation and User Manual

40 Operation

Figure 11 - Control signal connections

1

25

1 - REMOTE EQL
2 - SENSING RG +
3 - SENSING RC ­ 4 - TEMPORARY RELEASE
5 - REMOTE HVSD RESET
6 - REMOTE HVSD
7 - RFA NC
8 - Not Connected
9 - FAN ALARM NC
10 - RFA COMMON
11 - FAN ALARM COMMON
12 - SHUNT +
13 - SHUNT ­ 14 - FAN ALARM NO
15 - RFA NO
16 - GROUND
17 - SENSE COMMON
18 - SENSE NC
19 - SENSE NO
20 - Not Connected
21 - Not Connected
22 - Not Connected
23 - Not Connected
24 - Not Connected
25 - Not Connected

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

5. Maintenance

The NT5C06D rectifier is virtually maintenance free. It requires periodic
float / equalize verification (once every six months) and air filter replacement
as required.

Note:

If the unit operates in a dusty environment the optional

air filter is recommended. It must be inspected and
changed, or thoroughly cleaned, at least every 12 months,
or sooner if the dust level is high.

CAUTION

Do not install a wet filter on the unit.

To remove the filter, simply unscrew it. Re-install it by reversing the
operation.

41

Float / equalize

The float/equalize voltage level of the rectifier can be verified and adjusted
with the rectifier in, or out of service. To verify the equalize setting point
with the rectifier out of service, proceed as follows:

Procedure 6 - Adjusting the float / equalize

Step Action

1 Open the DC circuit breaker.
2 Put the FLT/EQL switch to the EQL position.
3 If the voltage requires readjustment use the EQL potentiometer to set the

equalize voltage to the new level.

4 Release the FLT/EQL to FLT.
5 Close the DC circuit breaker.

continued

Helios Rectifier 25/48NT5C06D Installation and User Manual

42 Maintenance

Procedure 6 - Adjusting the float / equalize ( continued )

Step Action

6 The float voltage should be adjusted with the rectifier in service, as follows:

The rectifier is connected to the system and should carry some load. If the
rectifier is connected in parallel with other rectifiers, verify that the total
system load current is shared equally among the rectifiers. If the current
reading is too low, or nil, slowly increase the FLT potentiometer, by turning it
clockwise, until sharing is achieved. If the current reading is too high, or the
unit is in the current limit mode, decrease the FLT potentiometer by turning it
counterclockwise.

High voltage shutdown (HVSD)

To verify or readjust the HVSD follow steps 5 to 8 of the “Rectifier Startup
and Verification” section of this manual.

Cooling fan

Visually inspect the airflow intake for any obstruction by foreign objects, or
excessive dust and dirt build-up. Open both the AC and DC breakers and
remove the rectifier from the power shelf. Inspect the air outlet for
obstruction by foreign objects, or excessive dust and dirt build-up. Visually
inspect the air outlet of the enclosure or cabinet. If a problem is detected in
the rectifier, contact your local Astec service facility. The unit is not designed
for on site servicing.

end

CAUTION

Do not attempt to access the inside of the unit with a tool
or a finger. Severe electrical shock could result.

Fan failure

If a fan alarm persists after the fan filter and assembly has been cleaned,
replace the fan assembly as follows:

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Fan replacement

Procedure 7 - Replacing the fan

Maintenance 43

CAUTION

Before replacing the fan, turn the rectifier OFF.
Completely disconnect and remove it from the shelf. Wait
thirty minutes to allow all internal capacitors to fully
discharge and for all components to cool down.

CAUTION

Keep any dirt, dust, moisture or metallic particles from
entering into the unit.

Step Action

1 Disconnect the 3-pin fan connector located below the fan assembly (refer

to Figure 12).

2 With the unit sitting solidly on a clean workbench, carefully remove the

four mounting screws that hold the fan assembly in place.

3 Slowly and carefully remove the fan assembly by pulling it from the

chassis.

4 Replace with a new one.

5 Mount the fan assembly in the same orientation as the old one. Ensure the

orientation of the fans is such that the air is blown outwards when the
fans are operated.

6 Mount the fan and fan grill using the four retaining screws.

7 Reconnect the fan connector.

8 Plug the unit back in and power it up. Holding a piece of paper at the front

of the unit should confirm that the air is pulled inwards from the front.

9 Listen carefully to detect any noise coming from the fans. They should run

freely. Verify that the fan alarm is OFF.

–end–

Helios Rectifier 25/48 Installation and User Manual

44 Maintenance

Figure 12 - NT5C06D rear view

CAUTION

Ensure that the fans spin freely, without interference.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Power shelf

CAUTION

Do not run the rectifier without a fully operational fan or
with a fan other than the specified replacement for this
cooling application.

The power shelf requires no maintenance.

Maintenance 45

Helios Rectifier 25/48 Installation and User Manual

46 Maintenance

This page is left blank intentionally.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

6. Troubleshooting

Alarm indication

RFA fault

Table 9 - System fault diagnosis

Fault symptom Possible causes

47

RFA

No AC input or input out of bounds.

No AC input or input out of bounds.

AC Input/DC output circuit breaker is open.

Rectifier has received a HVSD signal from the

controller.

An internal high voltage shutdown (HVSD) has
occurred. The internal High voltage shutdown point set too
low (below float or equalize setting).

Excessive impedance in one or both sense leads.

The cooling fan is failed.

DC circuit breaker is open.

A thermal shutdown has occurred.

Defective unit.

Excessive ambient air temperature.

Air inlet/outlet blocked, clogged air filter.

Helios Rectifier 25/48NT5C06D Installation and User Manual

48 Troubleshooting

SEN FAIL fault

Fault symptom Possible causes

SEN FAIL

Erratic load fault

Fault symptom Possible causes

Erratic load

Current or voltage float fault

Fault symptom Possible causes

Current or voltage
float

One or both remote sense leads is disconnected.

DC breaker is open.

Rectifier is still in walk-in.

Sense leads are reversed.

Requirement exceeds total rectifier capacity.

With paralleled units, the float and/or equalize is

misadjusted causing one or more units to carry the load.

Unit is in 'equalize' mode and paralleled units are not.

Remote sense lead has excessive impedance or are not

connected on one or more rectifiers.

System batteries are in a recharge mode after AC

outage.

Current share mode selection is not the same for all

units.

Forced share line is disconnected. (in FS only)

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

7. Appendix A: Replacement parts

ITEM CPC

Fan Assembly P0710139
Air Filter Kit P0834732

49

Helios Rectifier 25/48NT5C06D Installation and User Manual

50 Appendix A: Replacement parts

This page is left blank intentionally.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

8. Appendix B: Technical service assistance

For technical assistance, 24-hours a day / 7 days a week, dial one of the
following toll-free numbers. This service complements the services offered
by field support organizations such as, the Emergency Technical Assistance
Service (ETAS), and the Installation Technical Assistance Service (ITAS).

Local toll-free prefixes

The following prefixes give access to toll-free numbers in various countries.
For further information please contact the local service provider.

Country Prefix

Australia 0011
Belgium 00
Brazil 0021
Denmark 00
Finland 00 or 990
France 00
Germany 00
Hong Kong 001
Ireland 00
Japan 001 (KDD)

041 (ITJ)

0061 (IDC)

Korea 001 (Korea Telecom)

002 (Dacom)

003 (Once)
Malaysia 00
Netherlands 00
New Zealand 00
Singapore 001
Switzerland 00
United Kingdom 00

51

Helios Rectifier 25/48NT5C06D Installation and User Manual

52 Appendix B: Technical service assistance

Toll-free technical assistance numbers

United States: 1-800-992-8417 Canada: 1-800-363-2288

In Europe: In Asia and the Pacific:

Austria 800-213-49156 Australia 800-213-49156
Belgium 800-213-49156 Hong Kong 800-213-49156
Denmark 800-213-49156 Japan 800-213-49156
Finland 800-213-49156 Malaysia 800-213-49156
France 800-213-49156 New Zealand 800-213-49156
Germany 800-213-49156 Philippines 1-800-1-110-0131
Ireland 800-213-49156 Singapore 800-213-49156
Italy 800-213-49156 South Korea 800-213-49156
Netherlands 800-213-49156 Taiwan 800-213-49156
Norway 800-213-49156
Sweden 800-213-49156
Switzerland 800-213-49156
United Kingdom *1 800-213-49156

In the Caribbean and Latin America
(CALA):

Bahamas 1-800-389-0081 Israel 800-213-49156
Barbados 1-800-534-0225
Brazil 08-1571-012288
Colombia 980-192288
Dominican
Republic
Jamaica 1-800-850-1755
Mexico 001-800-514-2288
Puerto Rico 1-888-680-2288
Trinidad &
Tobago

*1

The United Kingdom includes England, Guernsey, the Isle of Man, Jersey, Northern

Ireland, and Scotland.

1-888-7514232

1-800-363-2288

In the Middle-East:

For countries not covered by a toll-free service dial Canada (country code

001) at 514−832−6707.

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

9. List of terms and acronyms

ALM Alarm

BAT Battery

53

BAT RT

C Common

CL Current Limit

CS Current Share

EMI Electromagnetic Interference

EQL Equalize

FAN ALM Fan Alarm

FLT Float

FR GND Frame Ground

FS Forced Load Share

HVSD High Voltage Shutdown

HVSDR High Voltage Shutdown Reset

LED Light Emitting Diode

LVA Low Voltage Alarm

LVD Low Voltage Disconnect

N Battery Return

LVDR Low Voltage Disconnect/Reconnect

MPA Modular Power Adapter

MPL Modular Power Low Voltage Disconnect

MPR Modular Power Rectifier

MPS Modular Power Shelf

MTBF Mean Time Between Failures

NC Normally Closed

Helios Rectifier 25/48NT5C06D Installation and User Manual

54 List of terms and acronyms

NO Normally Open

NT Northern Telecom

PCB Printed Circuit Board

RFA Rectifier Fail Alarm

RG+ Sensing Battery Positive

RC - Sensing Battery Negative

SEN FAIL Sense Fail

SH + Shunt Positive

SH - Shunt Negative

SLS Slope Load Sharing

TBD To be Determined

THSD Thermal Shutdown

TR Temporary Release

UM5C06D ( 169-2071-504 ) P0831010 Standard 7.00 May 2001

Helios Rectifer 25/48 Single Phase −48 V, 25 A
Power Factor Corrected Switch Mode Rectifier
NT5C06D

Installation and User Manual

Astec Advanced Power Systems Ltd
2280 Alfred-Nobel Blvd
St-Laurent ( Quebec ) Canada
H4S 2A4

Copyright  2001 Astec Advanced Power Systems Ltd
All Rights Reserved

The information contained in this manual is the property of Astec Advanced Power Systems
and is subject to change without notice. Astec Advanced Power Systems Ltd reserves the right
to make changes in design or components as progress in engineering and manufacturing may
warrant. Except as specifically authorized in writing by the V.P. of Engineering and Product
Manufacturing of Astec Advanced Power Systems Ltd, the holder of this manual shall keep all
information contained herein confidential and shall protect same, in whole or in part, from
disclosure and dissemination to all third parties, and use the same for start-up, operation,
troubleshooting, and maintenance purposes only. Any modification to the equipment must be
approved by the person responsible for product safety, and design quality at Astec Advanced
Power Systems Ltd to ensure that the equipment complies with the operation standards.

This equipment generates, uses, and can radiate radio frequency energy, and if not installed
and used in accordance with the instructions contained in the Installation and User Manuals,
can cause harmful interference to radio communications. Operation of this equipment in a
residential area is likely to cause harmful interference, in which case the user w ill be required
to correct the interference at his own expense.

Astec Advanced Power Systems
A part of Emerson Network Power

Helios Candeo is a trademark of Astec International Ltd. The Emerson logo is a trademark and
service mark of Emerson Electric Co.

Manual Number : UM5C06D ( 169-2071-504 )
Manual Issue : 7.00
Manual Status : Standard
Release Date : May 2001
P0831010

Published in Canada