Emerson Liebert NPS User manual

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Network Power Switch
Liebert NPS
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In ns st ta al ll la at ti io on n a an nd d U Us se er r M Ma an nu ua al l
Manual Reference: 6390060O-En (03/04) Rev ENPAu 05/2004

Dear Customer,
Please accept our thanks for giving us the privilege to serve you by choosing a Liebert make
product.
If this is your first Liebert product, we hope it is the beginning of a long relationship which
delivers value to your organisation. If you already own and use a Liebert product, we are
doubly honoured by your decision of continuing this relationship.
It is our constant endeavour to partner you for the growth and success of your business. This
philosophy is reflected in our Mission statement “To deliver value through Air & Power
Quality solutions to achieve customer delight”. Please do give us feedback to help us
realize our Mission.
EMERSON NETWORK POWER

ENGLISH
This manual describes installation and operation procedures for the
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All relevant parts of the manual should be read prior to commencing installation.
If you encounter any problems with the procedures contained in this manual
you should seek immediate assistance from the Liebert Sales Office
from whom the equipment was purchased.
Alternatively, contact the Liebert's Customer Service & Support department
at the address shown below:
Emerson Network Power Ltd - United Kingdom
Fourth Avenue, Globe Park
Marlow
Buckinghamshire SL71YG
United Kingdom
Telephone [phone]
Fax [phone]
Liebert HIROSS Services (HQ)
Customer Service and Support Department
Via Leonardo da Vinci 8
35028 - Piove di Sacco (PD)
Italy
Help Desk Telephone [phone]
Fax [phone]
[email protected]
Please visit our web site: http://ups.liebert-hiross.com/
While every precaution has been taken to ensure accuracy and comleteness in this manual, Liebert Corporation
assumes no responsibility and disclaims all liability for damages resulting from use of this information or for
any errors or omissions.
Liebert Corporation pursues a policy of continual product development and reserves the right to change the
equipment design without notice.
 Copyright 2004 by Liebert Corporation.
Unauthorized reproduction prohibited
All rights reserved.
(03/04) Page i

USER MANUAL
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Safety Precautions
CONFORMITY AND STANDARDS
This equipment complies with the following requirements:
Normative references:
The equipment must be installed in accordance with these instructions and used only with accessories approved
by the manufacturer to maintain conformity with the standards.
Safety:
* EN 50178
EMC:
* EN61000-6-2 (2001-10;immunity)
* EN6110
0
-6-3
(
emission
)
WARNING
Follow these instructions scrupulously:
The NPS is designed exclusively for indoor use. Protect the unit from excessive condensation and install it in a
place free of flammable liquids, gases and corrosive substances.
The Network Power Switch must be commissioned and serviced by an engineer approved by the manufacturer (or
his agent). Failure to do so could result in personnel safety risk, equipment malfunction and invalidation of
warranty.
Personnel working with the equipment described in this manual must be thoroughly familiar with the product.
Obtain appropriate protection against input overcurrents on the basis of the unit’s nominal power.
Before making connections rear the unit, make sure that all incoming power sources are de-energised and
insulated.
The unit is powered by more than one power mains.
As with other types of power equipment, dangerous voltages are present within the Network Power Switch
enclosure.
No risk exists to any personnel when operating the equipment in the normal manner, following the recommended
operating procedures.
General
The unit must be grounded in accordance with current electrical regulations.
Guide to the Instructions
The warning triangle indicates all the personal safety instructions.
Follow these instructions carefully to avoid injury.
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USER MANUAL
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Table of Contents
1 Chapter 1 – General description ............................................................................................................................... 1-1
1.1 Introduction ............................................................................................................................................................... 1-1
1.2 Design Concept ......................................................................................................................................................... 1-2
1.3 Mechanical Design Description................................................................................................................................ 1-3
1.4 Mimic Indications ..................................................................................................................................................... 1-4
1.5 Manual Bypass Switch Operation ............................................................................................................................ 1-5
1.6 Potential free contacts ............................................................................................................................................... 1-6
2 Chapter 2 – Operating Instructions........................................................................................................................... 2-1
2.1 Introduction ............................................................................................................................................................... 2-1
2.2 General Notes............................................................................................................................................................ 2-1
2.3 Procedure for Switching the Network Power Switch to power the load from a Power Off condition................... 2-1
2.4 Switching the Load to Manual Bypass condition..................................................................................................... 2-2
2.5 Procedure for switching the Network Power Switch from Manual Bypass condition to Normal Operation......... 2-2
3 Chapter 3 – Installation Procedure ........................................................................................................................... 3-1
3.1 Introduction ............................................................................................................................................................... 3-1
3.2 Equipment positioning and environmental considerations ...................................................................................... 3-1
3.3 Connecting cables to Network Power Switch .......................................................................................................... 3-2
3.3.1 Cable entry ....................................................................................................................................................... 3-2
3.3.2 Cable Rating..................................................................................................................................................... 3-2
3.3.3 Cable connections ............................................................................................................................................ 3-2
3.3.4 Safety earth....................................................................................................................................................... 3-2
3.3.5 Protective devices............................................................................................................................................. 3-3
3.3.6 Cabling Procedure............................................................................................................................................ 3-3
4 Chapter 4 - Specifications......................................................................................................................................... 4-1
4.1 Conformity and Standards ........................................................................................................................................ 4-1
4.2 General Specifications .............................................................................................................................................. 4-1
4.3 Environmental specifications.................................................................................................................................... 4-1
4.4 Electrical Specifications............................................................................................................................................ 4-2
4.5 Mechanical specifications ......................................................................................................................................... 4-2
5 Installation Drawings ................................................................................................................................................ 5-1
5.1.1 Power Circuit Diagram .................................................................................................................................... 5-1
5.1.2 External Power cable connections ................................................................................................................... 5-1
5.1.3 Overall general arrangement............................................................................................................................ 5-1
5.1.1 Power Circuit Diagram .................................................................................................................................... 5-2
5.1.2 External Power cable connections ................................................................................................................... 5-3
5.1.3 Overall general arrangement............................................................................................................................ 5-4
6LIMITED WARRANTY.......................................................................................................................................... 6-1
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USER MANUAL
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This manual describes the following equipment:
EQUIPMENT PART NUMBER
6 kVA Pole Network Power Switch SSWITCH-25A
Important
Support Information:
If you require assistance for any reason, please have the following information available:
Model and size
Serial number
Date installed
Location
Voltage & Frequency
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User Manual Chapter 1 - General Description
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1 Chapter 1 – General description
1.1 Introduction
The Network Power Switch is an automatic static transfer switch designed to provide fast automatic transfers between
two independent, synchronous AC power sources to provide continuity of AC power to critical equipment, such as
information technology equipment.
One of the two AC inputs is designed as the “preferred” source to which the Network Power Switch will connect the
load as long as the designated input source is within the acceptable limits, the Network Power Switch is designed to
transfer the output load to the “alternate “input source, as long as the alternate source is within the acceptable voltage
limits.
The Network Power Switch provides fast, break-before-make transfers to prevent interconnection of the two sources,
even under faulted source conditions.
The maximum sense and transfer times are within the tolerance of IEEE Standard 446 susceptibility curve for
information technology equipment to allow uninterrupted load equipment operation.
In case of overload, Network Power Switch gives the alarm. Under Short-circuit condition a fast acting semi conductor
fuse protects condition of the load.
Manual Bypass Switch
The entire power static switch module is hot swappable. Before removing this module the load is transferred, without
break to any one of the source directly by using the Manual bypass switch. After replacing the static switch module, the
load is restored on static switch module, using the Manual bypass switch.
Block Diagram
L1 BYP.
L2 BYP.
LINE
SIDE
ST. SW.
L1
L2
MAN. BYP. SW
N2 BY P.
N2 BY P.
NEUTRAL
SIDE
ST. SW.
N1
N2
MAN. BYP. SW
OUTPUT
NETWOR K POW ER SWIT CH
Fig 1.1 – Block Diagram of Network Power Switch
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Chapter 1 - General Description User Manual
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1.2 Design Concept
Figure 5.1.1 in Chapter 5 shows the Power circuit diagram for Network Power Switch. Source 1 & Source 2 are the
two synchronized power sources with fuse switches FS1 & FS2 & pair of SCR’s TA1 & TB1 in series with each path
&TA2 and TB2 in the neutral path
Logic dictates that at any time only one pair of back-to-back connected SCR’s in the line and neutral should conduct.
This routes the input power to the output load. Should the load feeding source fail due to any reason; the other source
takes over automatically in less than 6 ms.
This ensures that the critical load always receives the power & changeover time is less than the tolerance limit set by
IEEE 446 (CBEMA curve) for information technology equipments. The change over is always with break, which
ensures that in no case two sources get paralleled.
Priority source can be selected through front panel switch. The live mimic on front panel indicates which source is on
priority & which is feeding the load. Figure 1.4 shows the details of live mimic panel.
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1.3 Mechanical Design Description
FIXED UNIT
HOT SWAPPABLE UNIT
Fig 1.3 – Hot swappable and Fixed Unit
The Network Power Switch consists of two modules.
Fixed module consists of the input and output connections and manual bypass transfer control switch.
Second module is hot swappable plug-in type with removable electronics & static switching module.
The bypass / transfer control switch is located on right side of the cabinet with a key lock to restrict access to qualified
or designated operators. The plug in module likewise contains locked latches to prevent unauthorized removal of the
module. The Network Power Switch is designed to allow replacement of the removable electronics /switching module
without having to de-energize the load equipment.
Entire power static switch module is hot swappable. Before removing this module the load is transferred without break
to any one of the source directly. After replacing the static switch module, the load is again transferred back to Network
Power Switch without break.
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1.4 Mimic Indications
S1 Healthy S1 Priority S1 Feeding
S2 Healthy S2 Priority S2 Feeding
Priority
Selection
Switch
Load on S1
Load on S2
OverLoad on Super Switch
Uns ync hro ni sed tra ns fer
Fig 1.4 – Mimic and LED Indications
LED INDICATION
Mimic indications: Ten LEDs are mounted on the mimic plate;
Glowing LED’s indicate the status of the Network Power Switch.
S1 Healthy: Source –1 is a healthy source and is well above the 10% under voltage setting.
S2 Healthy: Source –2 is a healthy source and is well above the 10% under voltage setting.
S1 Priority: The priority selector switch is on S1 priority position.
S2 Priority: The priority selector switch is on S2 priority position.
S1 Feeding: The load is fed through source –1.
S2 Feeding: The load is fed through source -2.
Overload: Overload has occurred i.e. current level crossed 110% of full load.
Unsynchronized: The sources are out of phase-synchronized window.
Load on S1: Source –1 is feeding the load.
Load on S2: Source –2 is feeding the load.
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1.5 Manual Bypass Switch Operation
YE L L OW L ED
(LOAD ON S2)
YE L L OW L ED
(LOAD ON S1)
BYP ASS ON S1 SOURCE
BYP ASS ON S2 SOURCE
OUTPUT
Fig 1.5 – Manual Bypass Switch Operation
Manual Bypass switch is used only when a fault occurs in the Network Power Switch and the control circuitry of the
Network Power Switch is to be checked. For doing this operation the load is connected to the bypass. For Normal
Operation, the position of the switch should be at Network Power Switch output position (i.e. horizontal)
If the load is to be fed through the source 1 Bypass, first it is to be unlocked and the knob should be rotated
upwards. To feed through source 2 bypass the knob is to be rotated downward.
A mechanical interlocking arrangement is provided on this Bypass switch, by which the Hot swappable unit can be
removed only when load is connected to bypass. In normal operation when the load is connected to Network Power
Switch, the Hot swappable unit cannot be removed.
Operating Network Power Switch in Normal Mode (load connected to Network Power Switch output)
• Unlock the Manual Bypass Switch with the key provided.
• Depending upon the available healthy source (i.e. either Source-1 or Source-2 ) select it by changing the
Manual Bypass Switch position.
• Unlock the sliding module
• Pull out the Hot swappable sliding module out of the Network Power Switch, which contains (SCR
assembly, control circuitry).
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Operating Network Power Switch in Bypass mode
• Insert the Hot swappable module into the Network Power Switch unit
• Lock the sliding module for preventing its accidental opening.
• Unlock the Manual Bypass Switch with the key provided
• Connect the Load output to Network Power Switch by changing the switch position to Network Power
Switch output.
• Depending on the priority switch, Load will get transferred to source-1, if the priority switch is on source1.
• The Static Switch output position LED will glow
1.6 Potential free contacts
The Network Power Switch status can be checked with the 37 pin D-type connector, located on the rear end. This is a
potential free contact, and gives following indications as shown in Table 1-1 –
Table 1-1
191837363517Unsy nc h
193416151433S2 Feed
191332313012S2 Healthy
19291110928S1 Healthy
1982726257S1 Feed
192465423Priority
192132120Overload
CommonNONCCommonNONC
Termination available of 37 pin D-type connectorStatus
191837363517Unsy nc h
193416151433S2 Feed
191332313012S2 Healthy
19291110928S1 Healthy
1982726257S1 Feed
192465423Priority
192132120Overload
CommonNONCCommonNONC
Termination available of 37 pin D-type connectorStatus
The pin details for this connector is shown in fig 1.6
1219 3456789101112131415161718
2037 21222324252627282930313233343536
1219 3456789101112131415161718
2037 21222324252627282930313233343536
Fig 1.6 – Pin details for 37 pin D-type Connector
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User Manual Chapter 2 – Operating Instructions
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Chapter 2 – Operating Instructions2
2.1 Introduction
The Network Power Switch can be considered to be in one of the three operating conditions:
• Normal Operation - All relevant power switches and fuses closed and the Load is connected to Network
Power Switch output
• Manual Bypass – The load is connected to the input supply directly.
• Shut down - All power switches are off and load is not operational.
2.2 General Notes
NOTE: All users controls and indicators mentioned in these procedures are identified in chapter1
For power connection details, refer to figure in Chapter 5.
2.3 Procedure for Switching the Network Power Switch to power the load from a Power Off
condition
This procedure should be followed when turning on the Network Power Switch from a fully powered down condition
-i.e. When the load is not being initially supplied at all. It is assumed that the installation is complete; the authorized
personnel have commissioned the system.
1. Select the priority to source1. Close the fuse FS1.
2. Check for the LED S1 healthy, S1 priority, S1 feed and LED load on source1 to glow.
3. Close the fuse FS2.
4. Check for the LED S2 healthy to glow.
5. Using priority switch transfer the load to source2, check this transfer does not affect the load.
6. Transfer the load to source 1 again and check this transfer does not affect the load.
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Chapter 2 – Operating Instructions User Manual
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2.4 Switching the Load to Manual Bypass condition
YE L L OW L ED
(LOAD ON S2)
‘ON’
YE L L OW L ED
(LOAD ON S1)
BYP ASS ON S1 SOURCE
BYP ASS ON S2 SOURCE
(LOAD CONNECTED TO THIS BYPASS)
OUTPUT
(NOT CONNECTED)
Fig 2.2 – Switching to Bypass
WARNING
This operation should be performed by Trained personnel only.
SWITCH TO YELLOW LED ‘ON’ POSITION ONLY.
1. By seeing the LED indication check which source is feeding.
2. Unlock the Bypass switch lock by the using the key provided.
3. Rotate the Manual Bypass switch in the direction of the source feeding the load as per the warning given on the
mimic.
4. Relock the Bypass switch, remove the key and keep it in original place.
2.5 Procedure for switching the Network Power Switch from Manual Bypass condition to
Normal Operation
1. Unlock the Bypass switch using the key provided.
2. Rotate the bypass switch knob to the Static switch output position, i.e. horizontal position.
3. Lock the Bypass Switch, remove the key and keep it in original place.
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User Manual Chapter 3 - Installation Procedure
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3 Chapter 3 – Installation Procedure
3.1 Introduction
WARNING
Do not apply electrical power to the Network Power Switch equipment before the arrival of the
commissioning engineer.
WARNING
The Network Power Switch equipment should be installed by a qualified engineer in accordance with the
information contained in this chapter and the drawing package shipped inside UPS cabinet.
This chapter contains information regarding the positioning and cabling of the Network Power Switch.
Because every site has its peculiarities, it is not the aim of this chapter to provide step-by-step installation
instructions, but to act as a guide to the general procedures and practices that should be observed by the
installing engineer.
3.2 Equipment positioning and environmental considerations
The Network Power Switch cabinets are designed to fit in standard 19-inch rack. In case of non-availability, it can be
kept on floor or as a tabletop item, with sufficient ground clearance.
The super switch module should be located in a cool, dry, clean environment with adequate ventilation to keep the
ambient temperature within the specified operating range.
WARNING
The Network Power Switch cabinet is connected with live voltages,
hence it should be located at safe place.
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3.3 Connecting cables to Network Power Switch
WARNING
BEFORE CABLING-UP THE NETWORK POWER SWITCH, ENSURE THAT YOU ARE AWARE OF
THE LOCATION AND OPERATION OF THE EXTERNAL ISOLATORS THAT CONNECT THE
NETWORK POWER SWITCH INPUT SUPPLY TO THE MAINS DISTRIBUTION PANEL.
CHECK THAT THESE SUPPLIES ARE ELECTRICALLY ISOLATED, AND POST ANY NECESSARY
WARNING SIGNS TO PREVENT THEIR INADVERTENT OPERATION.
3.3.1
3.3.2
Cable entry
Cable enter the Network Power Switch cabinet, from the rear side as shown in figure 5.1.2. The cables are terminated
on the connectors and fuses.
Cable Rating
Following are the recommended cable size for 6kVA Network Power Switch –
Table 3-1
Description Max. Current rating (Amp) PVC cable (sq.mm)
Input Cables 25 4
Output Cables 25 4
Earthing - 2.5
Note:
These recommendations are for guideline purposes only and may be superseded by local regulations and codes
of practices.
3.3.3
3.3.4
Cable connections
Following are the set of external power cables, which are connected to the Network Power Switch equipment –
• Input source 1 – Line
• Input source 2 – Line
• Input source 1 – Neutral
• Input source 2 – Neutral
• Output – Line
• Output – Neutral
• Earthing
These cables are connected to the terminals on rear side of the equipment as shown in figure 5.1.2 in Chapter 5.
Safety earth
The safety earth busbar is provided on the rear side of equipment .The safety earth cable must be connected to this
busbar.
WARNING
FAILURE TO FOLLOW ADEQUATE EARTHING PROCEDURES CAN RESULT IN ELECTRIC
SHOCK HAZARD TO PERSONNEL, OR THE RISK OF FIRE, SHOULD AN EARTH FAULT OCCUR.
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3.3.5 Protective devices
For safety reasons, it is necessary to install external to the Network Power Switch system, circuit breaking protective
devices in the input a.c. supply and towards the output. Given that every installation has its own characteristics, this
chapter provides general useful information for qualified installation engineers, with knowledge of operating practices,
of regulatory standards, and of the equipment to be installed.
Rectifier and Bypass input supply of the Network Power Switch:
The input to Network Power Switch should be given through a 32 amp, 2pole ELCB for safe operation.
Protection against excessive overcurrents and short circuits in the mains supply input:
These inputs must be protected, installing suitable protective devices at the distribution panel of the incoming main
supply, considering that the protection should discriminate with overload capacity of the system.
The protective devices must be selected for the nominal input current, with respect to the rating and the input a.c.
supply voltage as given in table 3-1.
Protection against earth faults (RCD or RCCB devices):
In the event of a differential (RCD) device being installed upstream of the input supply, one must take into account the
transient and steady state earth leakage currents that are produced during start-up of the Network Power Switch.
The presence of an RFI suppression filter inside the NPS, determines a residual earth current not greater than 3.5 mA.
Residual current circuit breakers (RCCB/RCD) must be sensitive to d.c. unidirectional pulses (class A) in the network
and insensitive to transient current pulses.
They are identified by the symbols respectively:
These isolators must have an average sensitivity, possibly adjustable between 10mA and 0,3A.
It is recommended that the selectivity with every differential switch be verified both upstream of the input distribution
board and downstream (towards the load).
Output of the System:
In the eventuality that an external distribution panel is used for load distribution, the selection of protective device must
provide discrimination with those that are used at the input to the Network Power Switch module.
3.3.6 Cabling Procedure
The external power cables should be connected to the terminals as shown in figure 5.1.2 in Chapter 5. Proper
termination labels are provided near each connector for ease of cabling.
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Chapter 3 - Installation Procedure User Manual
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