Liebert Nfinity Maintenance Bypass Cabinet User Manual

POWER AVAILABILITY

Maintenance Bypass Cabinet for Nfinity

USER MANUAL

i

TABLE OF CONTENTS

IMPORTANT SAFETY INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

GLOSSARY OF SYMBOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Standard Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

FRONT VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

FRONT VIEW (WITH TRANSFORMER). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

REAR VIEW (WITHOUT TRANSFORMER) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

REAR VIEW (WITH TRANSFORMER). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

MODES OF OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

UPS Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Bypass Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

MAJOR COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Bypass Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

User Selectable Output Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

PREPARATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Required Setup Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Site Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

UNLOADING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Unloading the Maintenance Bypass Cabinet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Stationary Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

CABLE INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Wiring Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Preparing Internal Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Dual Source Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Removing the Cover Plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Power Cable Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

REPO Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Input Wiring (TB1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Maintenance Bypass Cabinet With Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Maintenance Bypass Cabinet Without Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

UPS to Maintenance Bypass With Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

UPS to Maintenance Bypass Without Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

OPERATING PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Start-Up and Initialization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Shutting Down the UPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Transferring System from UPS to Maintenance Bypass Operation. . . . . . . . . . . . . . . . . . . 18

Transfer of the System from Maintenance Bypass to UPS Operation. . . . . . . . . . . . . . . . . 18

MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Proper Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Scheduled Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Replacing Fan Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

1

IMPORTANT SAFETY INSTRUCTIONS

SAVE THESE
INSTRUCTIONS

This manual contains important instructions that
should be closely followed during installation and
maintenance of this Maintenance Bypass Cabinet.

This product is designed for commercial/ industrial
use only. this product is not intended for use with
life support and other designated “critical” devices.
Maximum load must not exceed that shown on the
UPS and the Maintenance Bypass Cabinet rating
label.

The Nfinity Maintenance Bypass Cabinet is
designed for use on properly grounded (earthed)
208/240 VAC 60 Hz supply, for installation by
qualified personnel. This UPS equipment is
intended to be installed by a qualified / certified
electrician who must review and approve customer
supplied wiring, circuit breakers, intended loads
and verify correct input, output and grounded
(earthed) connections to ensure compliance with
technical standards and national and local
electrical codes. Installation instructions and
warning notices are located in the Installation
section of this manual.

Operate the UPS equipment in an indoor
environment only in an ambient temperature range
of 32°F to 104°F (0°C to 40°C). Install it in a clean
environment, free from conductive contaminants,
moisture, flammable liquids, gases, or corrosive
substances.

Never block or insert any object into the ventilation
holes or other openings.

!

WARNING

LETHAL VOLTAGES MAY BE
PRESENT WITHIN THIS UNIT
EVEN WHEN IT IS APPARENTLY
NOT OPERATING. OBSERVE ALL
CAUTIONS AND WARNINGS IN
THIS MANUAL. FAILURE TO DO
SO MAY RESULT IN SERIOUS
INJURY OR DEATH. NEVER
WORK ALONE.

!

CAUTION

To reduce the risk of fire:

• The NMB1x and NMB4x models
must be connected to a circuit
provided with 100 amperes
maximum branch circuit
overcurrent protection in
accordance with applicable
national and local electrical
codes.

• The NMB5x and NMB8x models
must be connected to a circuit
provided with 125 amperes
maximum branch circuit
overcurrent protection in
accordance with applicable
national and local electrical
codes.

2

GLOSSARY OF SYMBOLS

Risk of Electrical Shock

Indicates Warning or Caution Followed by Important
Instructions

AC Input

AC Output

Requests the user to consult the manual

Equipment Grounding Conductor

ON

OFF

i

3

GENERAL DESCRIPTION

Congratulations on your purchase of Liebert’s
Nfinity™ Maintenance Bypass Cabinet with
Configurable Output Distribution. As with every
Liebert product, we stand behind our quality. If you
have any questions concerning this Maintenance
Bypass Cabinet, please feel free to contact your
local dealer, Liebert representative, or call the
appropriate Technical Support number listed on
the back of this manual.

To ensure proper installation and operation of this
unit, please read this manual thoroughly.

Installation must be done by a qualified/ certified
electrician, but general operation may be
performed without special training.

SYSTEM DESCRIPTION

The Liebert Nfinity Maintenance Bypass Cabinet is
intended for use with the Nfinity UPS. Typical
applications include supporting workstations,
servers, network, telecom or other sensitive
electronic equipment.

The Nfinity Maintenance Bypass Cabinet was
designed to provide maximum system availability
to business critical equipment. The Nfinity
Maintenance Bypass Cabinet allows for transfer of
connected loads to an alternate power path
allowing full isolation of the UPS. The UPS can
then be turned “OFF” and removed from service
with no interruption of power to connected loads.

Features

• Supports up to 20 kVA loads

• High speed transfer switch

• Compact design

• Highly configurable

• Multiple power path indicators

Standard Components

• Casters and leveling feet

• Easily accessible terminal blocks

• Supports Lockout/Tagout Program

• Support/mounting brackets for additional
stability

• Provisions for hardwire output

• Dual-source compatible for increased
availability

Options

• Output transformer for isolation

• Field installable output distribution

4

FRONT VIEW

Bypass availability

indicator (amber)

Cooling fans
(transformer models
only)

UPS input power

present (amber)

UPS output availability
indicator (green)

Bypass switch (SW1)

UPS input switch (SW2)

Support bracket

Output breaker (CB1)

5

REAR VIEW (WITHOUT TRANSFORMER)

Configurable output

distribution (optional)

Hardwire output

(standard)

Maintenance

bypass input (TB1)

UPS output (TB4)

Maintenance
bypass input (TB2)

UPS input (TB3)

Support bracket

Hardwire output
terminal block (TB5)

6

REAR VIEW (WITH TRANSFORMER)

Hardwire output
terminal block (TB6)

Configurable output

distribution (optional)

Hardwire output

(standard)

Maintenance bypass

input (TB1) (TB2)

UPS output (TB5)

UPS input (TB3)

Tap selector (TB4)

Support bracket

7

MODES OF OPERATION

The Nfinity Maintenance Bypass Cabinet is
designed to operate in the following modes:

UPS MODE

While the Nfinity Maintenance Bypass Cabinet is
in the UPS Mode, the UPS is supplying the
connected load with continuous high quality AC
power. In this mode of operation, the load is
protected by the UPS. The Bypass Switch rotated
toward the green lamp indicates this mode.

BYPASS MODE

When the Nfinity Maintenance Bypass Cabinet is
in the Bypass mode it provides an alternate path
for power to the connected equipment. Should the
UPS need to be taken out of service for limited
maintenance or repair, manual activation of the
bypass will cause an immediate transfer of the
equipment from the UPS inverter to the bypass
source. The amber lamp illuminated in the
Maintenance Bypass Switch compartment
indicates bypass is available. In this mode of
operation the load is NOT protected by the UPS.
The Bypass Switch rotated toward the amber lamp
indicates this mode. See OPERATING
PROCEDURES on page 18 for instructions on
use.

UPS ouput
available
(green)

Bypass mode

Bypass

available

(amber)

UPS Input source (amber)

ON = AC power supplied to UPS input
OFF = AC power removed from UPS input

8

MAJOR COMPONENTS

The following is a general description of each
component and its functions. Please review this
section carefully, as it will give you a better
understanding as to how the Nfinity Maintenance
Bypass Cabinet operates.

BYPASS SWITCH

The Bypass Switch allows easy and rapid transfer
of connected loads between the UPS and Bypass
source.

User Selectable Output Distribution

Several receptacle and hardwire options are
available as user selectable output distribution.
These are factory configured when ordered and
also allow for field upgrades. Common receptacle
and hardwire options include:

15 Amp Options

5-15R2
L5-15R2
6-15R2-208
6-15R2-240
L6-15R2-208
L6-15R2-240
15A,120V, 1 pole breaker w/ 1/2" & 3/4"

knockouts
15A,208V, 2 pole breaker w/ 1/2" & 3/4"

knockouts
15A,240V, 2 pole breaker w/ 1/2" & 3/4"

knockouts

20 Amp Options

5-20R2 (T-slot)
L5-20R
L6-20R-208
L6-20R-240
L14-20R-240
20A,120V, 1 pole breaker w/ 1/2" & 3/4"

knockouts
20A,208V, 2 pole breaker w/ 1/2" & 3/4"

knockouts
20A,240V, 2 pole breaker w/ 1/2" & 3/4"

knockouts

30 Amp Options

L5-30R
L6-30R-208
L6-30R-240
L14-30R-240
30A,120V, 1 pole breaker w/ 1/2" & 3/4"

knockouts
30A,208V, 2 pole breaker w/ 1/2" & 3/4"

knockouts
30A,240V, 2 pole breaker w/ 1/2" & 3/4"

knockouts

Other Options

Single Position Blanking Plate
Hardwire Option

Optional Transformer

Models offering a transformer are designed to
accept the same input voltage as the UPS and
provide 240 / 208 / 120 / 120 output. Models with
transformers are provided with redundant cooling
fans and user serviceable fan filters. The fans only
operate when in Bypass mode.

9

PREPARATION

These installation instructions provide all the
information needed for positioning the Nfinity
Maintenance Bypass Cabinet (including
environmental requirements) and for connecting
the input and output power cables.

INSPECTION

Upon receiving the Nfinity Maintenance Bypass
Cabinet, examine the packaging for any signs of
mishandling or damage. If any damage is noted,
contact your local dealer or Liebert representative
and notify your carrier.

ENVIRONMENT

The Maintenance Bypass Cabinet environment
must be free of conductive contaminants and
excessive moisture (water condensation),
flammable vapors, chemical fumes, or corrosive
gases and liquids.

REQUIRED SETUP EQUIPMENT

The tools below are required in order to properly
setup your maintenance bypass cabinet:

• pallet jack

• 1/2" (13 mm) wrench

• torque wrench

• flat-head screwdriver

• #2 Phillips screwdriver

• 3/16" (5 mm) Allen wrench

SITE PREPARATION

When deciding where to locate your Maintenance
Bypass Cabinet, consider the weight and size of
the unit. Make sure that the structural integrity of
the floor can withstand the weight. Refer to the

table below for dimensional considerations:

Check to make sure that your Maintenance
Bypass Cabinet will be located in a well-ventilated
area with at least 12 inches in front of and behind
it. Transformer based models are forced air cooled
with the aid of two internal cooling fans.

The unit frame is bolted to the shipping pallet to
ensure safety. It is recommended that a pallet jack
be used to transport the unit to its operating
location (prior to unbolting the unit).

Dimensions

Model w/Transformer w/oTransformer

W x D x H
In (mm)

9.5 x 26.5 x 30.4

(241.3 x 673.1 x 772.16)

Weight 287 lbs (130 kg) 85 lbs (38 kg)

12" (304mm)

12" (304mm)

10

UNLOADING

UNLOADING THE MAINTENANCE
B

YPASS CABINET

1. Once the Maintenance Bypass Cabinet is near
the desired operating location, remove the
cardboard cover.

2. Use a 1/2" (13mm) wrench to remove the eight
mounting bolts (four per bracket) from the
pallet brackets. Remove mounting brackets
from the pallet and Maintenance Bypass
Cabinet. Keep brackets and bolts for future
transportation of the Maintenance Bypass
Cabinet or for securing the cabinet to the floor.

3. Remove the metal ramp from the bottom of the
pallet, rotating it 180°. Fit ramp onto opposite
side of pallet (in slot) as shown below.

4. Using two people, slowly roll the Maintenance
Bypass Cabinet down the ramp until the
Maintenance Bypass Cabinet is on a level
surface.

!

CAUTION

This Maintenance Bypass Cabinet
is heavy (see weight in Dimensions
table on page 9). At least two
people should assist to unload it
from the pallet.

11

5. Once the Maintenance Bypass Cabinet is in
the desired location, adjust the leveling feet to
secure its position.

STATIONARY MOUNTING

Additional stability can be added by bolting the
mounting brackets (used in shipping) to the floor.

For greater stability, use a higher-grade bolt. Refer
to the dimensions below when drilling holes for
stationary mounting.

4-3/4"

(120 mm)

center line

28"

(711 mm)

5/16" diameter
6 places

4-3/4"

(120 mm)

12

CABLE INSTALLATION

WIRING PREPARATION

Be sure that the unit is not connected to any AC
mains power source or UPS before installing any
wiring to this unit. This Maintenance Bypass
Cabinet should be installed by a qualified / certified
electrician.

Preparing Internal Wiring

The Maintenance Bypass Cabinet is factory­configured for single-source installations. If your
installation requires dual-source capabilities, the
Maintenance Bypass Cabinet’s wiring must be
modified.

Dual Source Configuration

Modifying the wiring consists of removing the
jumpers between TB1 and TB2 as described
below:

1. Remove cover plates.

2. Identify TB1 and TB2.

3. Using a 3/16" Allen wrench, loosen terminal
mounting jumpers between TB1 and TB2.

4. Remove jumpers and retighten terminals to
22-26 in-lb (2.5 to 3.0 Nm).

5. Connect primary source to TB2 and secondary
source to TB1.

!

WARNING

PLEASE READ THIS SECTION
THOROUGHLY BEFORE
ATTEMPTING TO INSTALL
WIRING TO THIS UNIT.

TRANSFORMER MODELS

TB1 TB2 TB3

Cables to be
removed

NON-TRANSFORMER MODELS

TB1 TB2

Cables to be
removed

13

REMOVING THE COVER PLATES

On the back of the Maintenance Bypass Cabinet,
cover plates are over the input and output
terminals. Remove these using a phillips
screwdriver. Keep screws and plates to one side.

POWER CABLE INSTALLATION

Refer to the chart below when selecting cables:

NOTES: If an output transformer is fitted, the
Nfinity Maintenance Bypass has a five-cycle inrush
current that is 10 times the rated output current.
This must be taken into account when selecting
the overload protection device at the AC input
supply distribution point. To avoid random tripping
on start up, it is recommended that the AC input
supply be protected with a circuit breaker capable
of withstanding this initial inrush.

Transient and steady state earth leakage currents
may occur when starting the equipment. This
should be taken into account when selecting
ground current detection devices, as these will
carry the earth leakage currents of both the UPS
equipment and the load.

REPO CONNECTION

Refer to the Nfinity user manual for connection
details.

Power Cable and Protection Ratings

Models NMB1x & NMB4x

Max Input Current

100 A

Input Protection

100 A

Max Output Current

100 A

Input/ Output Terminal
Details

Max: 2/0 (70 mm

2

)

Min: 6 AWG (16 mm

2

)

Models NMB5x & NMB8x

Max Input Current

125 A

Input Protection

125 A

Max Output Current

125 A

Input/ Output Terminal
Details

Max: 2/0 (70 mm

2

)

Min: 6 AWG (16 mm

2

)

14

INPUT WIRING (TB1)

Connect the input wiring as stated in the following
steps:

1. Locate the input wiring access, remove the
knockout and pull the three/four input wires
through it, allowing some slack for installation.

2. Secure the conduit to the rear panel of the
Maintenance Bypass Cabinet.

3. Input power cables connect to hex terminals
on the input terminal block.

4. Insert the ground (earth) wire through the
earth lug and tighten it to the proper torque
value (22-26 in-lb). Then connect the wires to
the block connections as shown below. Using
a torque wrench, turn the screws clockwise
until tightened to the proper torque value
(22-26 in-lb).

NOTE

Input wiring must be installed using
conduit.

208 input voltage jumper—if only the
connections for 208 VAC are made
between the UPS and theNfinity
Maintenance Bypass, the 208 input
voltage jumper must be installed for
proper operation. To install this jumper,
place the jumper wire provided in the
accessory kit between Pin 1 and Pin 2 on
TB4.

Input

Conduit

RIGHT HAND OPTION

( LOOKING FROM FRONT OF UNIT )

REAR VIEW

LEFT HAND OPTION

( LOOKING FROM FRONT OF UNIT )

REAR VIEW

15

Maintenance Bypass Cabinet With Transformer

Maintenance Bypass Cabinet Without Transformer

SW2

UPS Input

Switch

Transformer

TB4

208/240V

Tap Selector

UPS Input UPS Output

Output

SW1

Bypass

Switch

CB1

Output

Breaker

TB5

TB2

TB3

TB6

Input 1

Input 2

TB1

Single input jumper
(remove for dual
input feeds)

Input 2

SW2

UPS Input

Switch

UPS Input UPS Output

Output

SW1

Bypass

Switch

CB1

Output

Breaker

TB4

TB2

TB3

TB5

Input 1

TB1

Single input jumper
(remove for dual input feeds)

16

UPS to Maintenance Bypass With Transformer

G

TB1

TB2

G

TB3 TB4

123

TB5

TB6

L1

L2

L1

L2

L1 L2 G 1 2 3 4

1

2

3

4

120

208

240

120

L1 L2 G 1 2 3 1 2 3 4 5

GEC

TB3TB2TB1

Flexible
conduit

208 240

NFINITY UPS

NFINITY MAINTENANCE BYPASS CABINET

WITH TRANSFORMER

Input 2

Input 1

See Nfinity
user manual
for details on
connecting
GEC.

G

G

G

NOTES

1. If feeding the Maintenance Bypass Cabinet from a single source, the input
connection may be made to either TB1 or TB2.

2. If feeding the Maintenance Bypass Cabinet from a dual source, the UPS input
supply connection must

be made to TB1 and the bypass input supply connection

must

be made to TB2. The link between TB1 and TB2 must be removed.

Remove these two
wires for dual source

Ensure that both tap
selectors are set to the
correct input voltage

17

UPS to Maintenance Bypass Without Transformer

G

TB1

TB2

G

TB3 TB4

TB5

L1

L2

L1

L2

L1 L2 G 1 2 3 4

1

2

3

4

120

208

240

120

L1 L2 G 1 2 3 1 2 3 4 5

GEC

TB3TB2TB1

Flexible
conduit

NFINITY UPS

NFINITY MAINTENANCE BYPASS CABINET

WITHOUT TRANSFORMER

Input 2

Input 1

N

N

See Nfinity
user manual
for details on
connecting
GEC.

G

G

G

NOTES

1. If feeding the Maintenance Bypass Cabinet from a single source, the input
connection may be made to either TB1 or TB2.

2. If feeding the Maintenance Bypass Cabinet from a dual source, the UPS input
supply connection must

be made to TB1 and the bypass input supply connection

must

be made to TB2. The link between TB1 and TB2 must be removed.

Remove these three
wires for dual source

Ensure that the tap
selector is set to the
correct input voltage

18

OPERATING PROCEDURES

START-UP AND INITIALIZATION

Follow these steps in order to start up the Nfinity
UPS while connected to the Nfinity Maintenance
Bypass.

1. Set Maintenance Bypass switch (SW1) to UPS
position on Maintenance Bypass Cabinet.

2. Close UPS source switch (SW2).

3. Close output circuit breaker (CB1).

4. Close input circuit breaker (CB1).

5. On UPS, close control enable switch (SW2).

6. After UPS has initialized, turn UPS output on
by pushing the standby button.

SHUTTING DOWN THE UPS

Use the following procedure to power down the
system.

1. Turn UPS output off by pushing the Standby
button.

2. Open the control enable switch (SW2) on the
UPS.

3. Open the input circuit breaker (CB1) on the
UPS.

4. Open the UPS source switch (SW2) on the
Maintenance Bypass Cabinet.

5. Open the output circuit breaker (CB1) on the
Maintenance Bypass Cabinet.

TRANSFERRING SYSTEM FROM UPS

TO MAINTENANCE BYPASS

O

PERATION

1. Verify that the amber bypass lamp is
illuminated

2. Turn the bypass switch (SW1) to the bypass
position on the Maintenance Bypass Cabinet.
The connected equipment is now powered
from the bypass source and is not protected.

TRANSFER OF THE SYSTEM FROM
M

AINTENANCE BYPASS TO UPS

O

PERATION

1. Close the UPS source switch (SW2) on the
Maintenance Bypass Cabinet.

2. Close the input circuit breaker (CB1) on the
UPS.

3. Close the control enable switch (SW2) on the
UPS.

4. Turn the UPS output on by pushing the
standby button on the UPS. Verify the Green
UPS lamp is illuminated.

5. Turn the bypass switch to the bypass position
on the Maintenance Bypass Cabinet.

19

MAINTENANCE

PROPER CARE

Keeping your Liebert Nfinity Maintenance Bypass
Cabinet operating properly is imperative to optimal
performance and life of the unit. It is
recommended that a certified technician perform
preventive and corrective maintenance. Liebert
Global Services (LGS) is dedicated to ensuring the
highest level of performance and unmatched
support for your Nfinity Maintenance Bypass
Cabinet. Contact an LGS representative for
services to guarantee maximum reliability and
system availability.

SCHEDULED MAINTENANCE

It is recommended that the following maintenance
be performed at least monthly:

• Check, clean and replace filters.

• Verify that airflow is not obstructed.

It is recommended that the following maintenance
be performed annually:

• Verify all power connections.

• Verify that all output distribution modules are
operating properly.

REPLACING FAN FILTERS

Transformer Models Only

The Maintenance Bypass Cabinet intake fans
contain filters that will need to be replaced or
cleaned periodically, depending on the
surrounding environment. Check by noting the
condition of the two filters. If filters are dirty,
replace or wash them. The filters may be taken out
of the UPS for replacement or cleaning by
removing the plastic cover over the filter frame.
Use caution when replacing filters when fans are
running.

The fan filters are washable and can be reused.
To wash these filters, place them under a running
faucet (with the dirt side down) to remove dirt and
dust. Blot dry with a towel and allow air-drying
before reusing.

Fan Filters

20

SPECIFICATIONS

General & Environmental Rating

Unit Rating

kVA

Models NMB1x and NMB4x = 18

Models NMB5x and NMB8x = 20

Amps

Models NMB1x and NMB4x = 100 max

Models NMB5x and NMB8x = 125 max

Compliant Safety Standards UL 1778, c-UL

Mechanical

Dimensions

Width

In (mm)

9.5 (241)

Depth 26.5 (700)

Height 30.4 (775)

Weight lb (kg)

287 (130)

transformer model

85 (39)

transformerless model

Environmental

Operating Temperature (max) F (C) 32º - 104º (0º - 40º)

Relative Humidity % 0-95% non-condensing

Maximum Operating Altitude Ft (M) 10,000 (3000)

Input Data

Nominal Input Voltage VAC 208 or 240

Input Frequency (nominal) Hz 60

Input Frequency Range Hz 55-65

Output Data 208/240 240 208

Output Voltage VAC 120/120/208/240 120/120/240* 120/120/208*

Transfer Time msec <4 msec typical

Output Frequency Hz 60

* Transformerless model requires neutral input

The Company Behind the Products

With over a million installations around the globe,
Liebert is the world leader in computer protection
systems. Since its founding in 1965, Liebert has
developed a complete range of support and
protection systems for sensitive electronics:

• Environmental systems—close-control air
conditioning from 1 to 60 tons

• Power conditioning and UPS with power
ranges from 300 VA to more than 1000 kVA

• Integrated systems that provide both
environmental and power protection in a
single, flexible package

• Monitoring and control—from systems of any
size or location, on-site or remote

• Service and support through more than 100
service centers around the world and a 24/7
Customer Response Center

While every precaution has been taken to ensure
the accuracy and completeness of this literature,
Liebert Corporation assumes no responsibility and
disclaims all liability for damages resulting from
use of this information or for any errors or
omissions.

© 2002 Liebert Corporation
All rights reserved throughout the world.
Specifications subject to change without notice.

® Liebert and the Liebert logo are registered
trademarks of Liebert Corporation. All names
referred to are trademarks or registered
trademarks of their respective owners.

SL-23960 (7/02) Rev. 2

Technical Support /Service

Web Site

www.liebert.com

Monitoring

800-222-5877

[e-mail]

Outside the US: 614-841-6755

Single-Phase UPS

800-222-5877

[e-mail]

Outside the US: 614-841-6755

Three-Phase UPS

800-543-2378

[e-mail]

Environmental Systems

800-543-2778

Outside the United States

614-888-0246

Locations

United States

1050 Dearborn Drive

P.O. Box 29186

Columbus, OH 43229

Italy

Via Leonardo Da Vinci 8

Zona Industriale Tognana

35028 Piove Di Sacco (PD)

[phone]

Fax: [phone]

Asia

23F, Allied Kajima Bldg.

138 Gloucester Road

Wanchai

Hong Kong

[phone]

Fax: [phone]

POWER AVAILABILITY

Maintenance Bypass Cabinet for Nfinity

USER MANUAL