socomec 16A User manual

IT-SWITCH®16A & 20A
INTELLIGENT TRANSFER SWITCH
16A AND 20A
USER'S GUIDE
UPS/NTA GB/ITS16.F
31/05/2010
IT-SWITCH (models B & E) - 16A & 20A

UPS/NTA GB/ITS16.F page 1/24
FOREWORD
We thank you for the trust you have in SOCOMEC UPS IT-SWITCH (models S, B and E).
Our equipment complies with:
- Electromagnetic compatibility directives as per standards EN 50081-1 and EN 50081-2,
- Low Voltage directives.
SAFETY REQUIREMENTS
Conditions:
Do read carefully these operation instructions before proceeding to the IT-SWITCH commissioning. For an
optimal use, it is recommended to:
- maintain the ambient temperature between 0°C and 35°C,
- maintain the humidity rate below 90% (condensation-free).
Precautions the user should take:
WARNING:
•It is absolutely necessary to earth the IT-SWITCH before connecting any upstream and downstream
supplies.
•Hazard remain present even if the IT-SWITCH output has been switched off ; supply voltage of sources 1
and 2 is indeed still present.
•Do not remove the cover without completely disconnecting the IT-SWITCH from the input supplies 1 and
2.
Do follow scrupulously the procedures when switching the IT-SWITCH on or off. Whatever the repairs, they
must be exclusively executed by authorised and skilled staff.
This equipment meets the requirements of the European directives applied to this product. Hence it is
labelled as follows:
This equipment is designed to a restricted distribution in compliance with the conditions defined by the
standard EN 50091-2. As a consequence, restrictions to the installation or complementary steps may be
needed to prevent potential electromagnetic interference.

UPS/NTA GB/ITS16.F page 2
Certificate of Warranty
This SOCOMEC UPS IT SWITCH is guaranteed against any defect in
construction or operation arising from faulty design or materials for a period of 12
months, valid from the date of purchase.
The warranty certificate must NOT be sent to the manufacturer but should be kept
in a safe place together with proof of purchase, as these will be required should
the product need to be repaired or replaced under the terms of the warranty.
The period of validity of the warranty is calculated from the date of purchase by the
end user from an authorised dealer (the date on the purchase document is
sufficient for this purpose).
The warranty is of the 'carry-in' kind: SOCOMEC UPS will provide parts and labour
free of charge for all repair work carried out, but the customer is responsible for
the cost and risk of transport to and from SOCOMEC UPS.
For these stipulations to be valid, the Purchaser must comply with the following:
- the product must only be returned in its original packing. Any damage caused to the
product during transport, where the original packing has not been used, is not
covered by the terms of this warranty.
- The product must be accompanied by proof of purchase (i.e. invoice, receipt)
stating the date of purchase and clearly identifying the product (i.e. bearing the
model and serial number). The repair return authorisation number is given by the
service centre over the phone after they have received a detailed description of the
fault. Failure to provide one of these means that the warranty is no longer valid.
- Should the customer not be able to provide proof of purchase, the serial number
and the date of manufacture will be used to calculate the warranty period. This may
mean the warranty period is shorter than it would otherwise be.
- The warranty does not cover damage due to misuse (use out of tolerances: power
supply, lightening, humidity, temperature, poor ventilation, etc.), tampering or any
other kind of non-authorised intervention.
- During the warranty period, SOCOMEC UPS liability is limited to the obligations as
defined herein (repair or replacement).

UPS/NTA GB/ITS16.F page 3
CONTENTS
1. PURPOSE OF THE IT-SWITCH.................................................................................................................................5
2. IT-SWITCH ARRANGEMENT...................................................................................................................................5
2.1. SUMMARY TABLE OF THE VARIOUS FUNCTIONS AVAILABLE ON MODELS S, BAND E................................................5
2.2. FIXED 19" RACK VERSION (MODELS SOR B) ...........................................................................................................6
2.3. HOT-SWAP 19" RACK VERSION (MODEL E)...............................................................................................................7
3. MAIN FEATURES........................................................................................................................................................8
3.1. CONNECTION MEANS ON THE REAR FACE:.................................................................................................................8
4. PRECAUTIONS UPON RECEIPT.............................................................................................................................9
5. GENERAL RECOMMENDATIONS FOR INSTALLATION.................................................................................9
6. ASSEMBLING MODELS "S", "B" OR "E" IN A STANDARD 19" CABINET..................................................9
7. SAFETY.......................................................................................................................................................................10
8. REAR PANEL OF THE FIXED IT-SWITCH (MODELS S OR B).......................................................................10
9. REAR PANEL OF THE HOT-SWAP IT-SWITCH (MODEL E)...........................................................................11
9.1. REAR PANEL EQUIPPED WITH SOCKETS 16 AOF IEC320 TYPE................................................................................11
9.2. REAR VIEW WITH TERMINALS (IT SWITCH 16A &20A).......................................................................................11
9.3. DETAILS OF CONNECTION TERMINAL ......................................................................................................................12
10. EXTERNAL COMMUNICATION LINKS............................................................................................................12
10.1. REMOTE TRANSFER THROUGH POTENTIAL-FREE CONTACTS .................................................................................12
10.2. REMOTE TRANSFER THROUGH SERIAL LINK ..........................................................................................................12
11. OPERATING PRINCIPLE......................................................................................................................................14
12. CONTROL PANEL ..................................................................................................................................................15
12.1. DESCRIPTION OF STATES AND ALARMS .................................................................................................................15
12.2. KEY CONTROLS.....................................................................................................................................................16
12.3. OPERATION EXPLANATIONS........................................................................................................................16
13. COMMISSIONNING - OPERATION....................................................................................................................19
13.1. PRELIMINARY CHECKS..........................................................................................................................................19
13.2. SAFETY -REMINDERS .........................................................................................................................................19
13.3. PRELIMINARY CONDITIONS...................................................................................................................................19
13.4. LOAD SUPPLY .......................................................................................................................................................19
13.5. CHANGING THE SOURCE PRIORITY (MODELS S, BAND E).....................................................................................19
13.6. LOAD DISCONNECTION .........................................................................................................................................20
13.7. TRANSFER TO MANUAL BYPASS (IT-SWITCH MODEL E)....................................................................................20
13.8. SEAMLESS REPLACEMENT OF THE ELECTRONIC RACK (IT-SWITCH MODEL E)....................................................21
14. DESCRIPTION OF THE VARIOUS STATES......................................................................................................22
14.1. TRANSFER IMPOSSIBLE .........................................................................................................................................22
14.2. IMMINENT SHUTDOWN..........................................................................................................................................22
15. GENERAL ALARM.................................................................................................................................................22
16. DIFFICULTIES DURING COMMISSIONING....................................................................................................23
17. MAINTENANCE ......................................................................................................................................................23
18. TROUBLE SHOOTING...........................................................................................................................................23

UPS/NTA GB/ITS16.F page 4
ABBREVIATIONS
IT-SWITCH : Intelligent Transfer Switch
SW : Switch
MODBUS/JBUS ® : Industrial communication protocol, APRIL registered brand
Note: Packaging – Data labels
1. Fixed 19'' standard rack version (model S)
The reference marked on the packaging and on the data labels: IT-SWITCH 16A MS.
2. Fixed 19'' HA rack version (model B)
The reference marked on the packaging and on the data labels: IT-SWITCH 16A MB.
3. Hot Swap 19'' rack version (model E)
The marking reference on the packaging is:
- IT-SWITCH 16A MET or IT-SWITCH 20A MET if the system is fitted with terminal connections,
- IT-SWITCH 16A MES if the system is fitted with sockets 16 A of IEC320 type.
The references on the data labels are as follows:
- IT-SWITCH 16A ET + serial number if the chassis is fitted with terminal connections,
- IT-SWITCH 16A ES + serial number if the chassis is fitted sockets 16A of IEC320 type,
- IT-SWITCH 16A ME or IT-SWITCH 20A ME + serial number for the hot swap rack.

UPS/NTA GB/ITS16.F page 5
GENERAL PRESENTATION
1. PURPOSE OF THE IT-SWITCH
The IT-SWITCH provides a dual redundant supply to the load(s) from two synchronous and alternating
sources.
The IT-SWITCH senses voltage outages and ensures the load automatically transfers to the alternate source
(seamless for the load).
The IT-SWITCH improves the load power supply reliability. The load can quickly be transferred (either
automatically or manually) from the so called "Preferred" source to the "alternate" source (and vice versa).
Note: this document provides information in terms of safety, connection and using.
2. IT-SWITCH ARRANGEMENT
Three versions of IT-SWITCH are available:
-fixed 19'' standard rack version (model S)
- fixed 19'' HA1rack version (model B)
-hot-swap 19'' rack version (model E), with a manual bypass for replacing the live IT-SWITCH without
interrupting the load power supply.
Both versions can be mounted in standard 19'' cabinets.
2.1. Summary table of the various functions available on models S, B and E
Standard
IT-SWITCH
HA IT-
SWITCH
Hot swap HA
IT-SWITCH
FUNCTIONS Model S Model B Model E
- Type of transfer:
manual
without sources
overlapping
synchronous/asynchronous
synchronous type only
- Detection of short circuit on the output
- Counter for successive transfers upon failure
- Hot Swap unit
- Manual by-pass
- Serial link (JBUS)
- Dry contacts
- Selection of priority source
- Event log
- Socket for commissioning and servicing PC
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
1High Availability
SECTION
1

UPS/NTA GB/ITS16.F page 6
2.2. Fixed 19" rack version (Models S or B)
OVERVIEW
Front: - Mimic panel
- Access door for connecting the
maintenance PC
- handles
Rear: connections through socket 16 A of
IEC 320 type - see section 8 for:
- source input
- output to the loads (4 output sockets).
Dimensions are mentioned in section 3.
BASIC SCHEME
SOURCE INPUTS
SW SW
TO THE LOADS

UPS/NTA GB/ITS16.F page 7
2.3. Hot-swap 19" rack version (Model E)
This version additionally comprises a chassis (19'' format) in which can be found the manual bypass switch.
The chassis accommodates the IT-SWITCH rack that can be removed without disconnecting the load supply.
Dimensions are mentioned in section 3.
OVERVIEW
A
B
AHot-swap IT-SWITCH rack including on the
front:
- the mimic panel,
- the access door to the manual bypass switch
and to the connection socket for maintenance
PC,
- the handles for pulling out the rack
BChassis including the MANUAL BYPASS and
rear connections.
BASIC SCHEME
INPUT SOURCES
SW SW
A
B
12
N
TO THE LOADS
AHot-swap IT-SWITCH rack with switching electronics.
B Fixed 19'' chassis with the manual bypass.

UPS/NTA GB/ITS16.F page 8
3. MAIN FEATURES
Electrical data and performance
Supply Single phase
Input voltages (source 1 and source 2) 120V-220V-230V-240V ±10 % rms
Rated frequency 50-60 Hz ±10 %
Phase tolerance admitted between
Source1/Source 2 for seamless transfer 15°
Max gradient for frequency variation 10 Hz/sec
Rated current 16A or 20A
Peak factor 4
Overloads
CURRENT Model S Models
B and E (16A) Models E (20A)
1,1 In 1h 3h 1h
1,25 In 10' 30' 10'
1,5 In 2' 6' 2'
2 In 10" 1' 10"
Ventilation Natural
Maxi ambient temperature 40° C
Humidity < 90 % condensation-free
Altitude 1000 m
Protection index IP 21
Mechanical data
Width 2
Depth 3
Height
Weight
Fixed models S and B 16A
446 mm
300 mm
131 mm
8,5 kg
Hot-swap model E 16A & 20A
449 mm
390 mm
133 mm
14 kg
3.1. Connection means on the rear face:
Connections are to be done on the rear panel of the IT-SWITCH.
The fixed IT-SWITCH (models S or B) is fitted with sockets 16A of IEC 320-type (see §8).
The hot-swap IT-SWITCH (model E) is fitted with either:
- screw terminals (IT-SWITCH 16A and 20A)
- sockets 16 A of IEC 320 type (IT-SWITCH 16A only).
2484 mm with fixing squares
3+ 10mm including screws and + 40mm including handles (overall dimension: + 50 mm)

UPS/NTA GB/ITS16.F page 9
INSTALLATION - CONNECTIONS
4. PRECAUTIONS UPON RECEIPT
Always inspect the packaging condition of the equipment upon receipt (in terms of damage, shocks, or
enclosure deformation).
If necessary, write down discrepancies on the delivery note.
Carefully extract the IT-SWITCH from its packaging, knowing that the weight is not evenly shared within the
case.
5. GENERAL RECOMMENDATIONS FOR INSTALLATION
The environment should:
- be protected by humidity,
- provide no obstacle to prevent air circulation, especially if the IT-SWITCH is located in a cabinet,
- allow sufficient ventilation to ensure a constant operating temperature,
- be dry, clean and dust free,
- be free of flammable vapour or corrosive smoke.
REMINDER : The ambient temperature recommended is between
0 and 35°C.
6. ASSEMBLING MODELS "S", "B" OR "E" IN A STANDARD 19" CABINET
The ensure proper assembling, the IT-SWITCH (models S, B or E) shall lie on the horizontal side fixing bars
in the cabinet (see fig. 1 marking A) or on the support brackets at the rear of the rack (see fig. 2).
Models S and B (fixed) is provided with assembling accessories (2 braces marked E241143) for fastening to
the front frame of the standard 19" cabinet (see fig. 3).
Model E (hot-swap) has a built-in fastening means on the chassis (see fig. 4).
Figure 1
A
A
Figure 3
Figure 2
Figure 4
SECTION
2

UPS/NTA GB/ITS16.F page 10
7. SAFETY
IMPORTANT
It is recommended to carefully read this manual prior to source and load
connections. This manual should be kept close to the IT-SWITCH for easy
consultation if needed.
CAUTION
For connections to terminals (IT-SWITCH model E):
EARTHING CONNECTIONS ARE TO BE MADE PRIOR TO SOURCE
CONNECTIONS.
IMPORTANT
ELECTRICAL CONNECTIONS AS WELL AS CABLING OPERATIONS
SHOULD ONLY BE MADE BY SKILLED AND SUITABLY TRAINED
PERSONNEL.
8. REAR PANEL OF THE FIXED IT-SWITCH (models S or B)
The rear panel comprises (see § 9.2.):
- 2 input male sockets IEC320 16A,
- 4 output female sockets IEC320 16A
- 2 hot-swap connectors with securing screws for external communication:
- X31 for alarm transfers through potential-free contacts (use twisted cables),
- X32 for remote transfers through serial link (use shielded twisted cables).
X31 X32
110 110
Details about the connection of IEC sockets:
INPUT SOURCE 1 – INPUT SOURCE 2 LOAD OUTPUT
SHIELD
CONNECTION
EXTERNAL COMMUNICATION
INPUT SOURCE 1 LOAD OUTPUT
4 sockets available
INPUT
SOURCE 2
PE: Electrical
protective conducteur
PHASE
NEUTRAL
PHASE
NEUTRAL
PE: Electrical
protective conducteur

UPS/NTA GB/ITS16.F page 11
9. REAR PANEL OF THE HOT-SWAP IT-SWITCH (MODEL E)
The rear panels can either comprise sockets 16 A of IEC 320 type or terminals.
Note: for the IT SWITCH 20A, connection is only by means of terminals.
9.1. Rear panel equipped with sockets 16 A of IEC320 type
The rear panel shows:
- 2 inputs male sockets IEC320 16A,
- 4 output female sockets IEC320 16A,
- 2 hot-swap connectors with securing screws for external communication:
- X31 for alarm transfers through potential-free contacts (use twisted pairs),
- X32 for remote transfers through serial link (use shielded twisted cables).
X31 X32
110 110
Please refer to section 8 for connections.
9.2. Rear view with terminals (IT SWITCH 16A & 20A)
Loosen the 6 screws on the rear panel to connection area.
The connection area includes the terminals and the connectors.
REAR PANEL
SHIELD
CONNECTION
EXTERNAL COMMUNICATION
ALARM TRANSFER
INPUT SOURCE 1 LOAD OUTPUT
4 sockets available
INPUT
SOURCE 2

UPS/NTA GB/ITS16.F page 12
9.3. Details of connection terminal (≤6 mm²)
123456 789
SOURCE 1
1 = Neutral
2 = Phase
3 = PE
SOURCE 2
7 = Neutral
8 = Phase
9 = PE
LOAD
4 = Neutral
5 = Phase
6 = PE
10. EXTERNAL COMMUNICATION LINKS
10.1. Remote transfer through potential-free contacts
Connector X31 is for remote transfer of the following states and alarms:
STATUS and ALARMS
Source 1 ON terminals 1-2, closing contact
Source 2 ON terminals 3-4, closing contact
Source 1 preferred terminals 5-6, closing contact
Transfer impossible terminals 7-8, closing contact
General Alarm terminals 9-10, contact closed upon failure
NOTE: breaking capacity of contacts: 0,5 A with 125VAC. Use twisted wires. These contacts are set to close
by default.
10.2. Remote transfer through serial link
Connector X32 enables the connection through the RS485 (or RS422) – type serial link under the
MODBUS/JBUS®protocol.
For address assignment, please refer to manual UPS/NTA GB/MTCJBUS.
X
31 X32
Connector to the chassis
on the IT-SWITCH rack Manual Bypass
switch Connection terminal to
SOURCES and LOAD External communication
Alarm
transfer
CONNECTION AREA

UPS/NTA GB/ITS16.F page 13
RS485 Link RS422 Link
On X32, strap terminals 1 and 2 if the IT-SWITCH
is line end. On X32, strap terminals 1 and 2 ; as well as 5 and 6 if the IT-SWITCH is line end.
terminal 2: TX+ / RX+ terminal 2: TX+
terminal 3: TX- /RX- terminal 3: TX-
terminal 7: 0V Isolated terminal 4: RX+
terminal 5: RX-
terminal 7: 0V Isolated
NOTE: Use shielded and twisted wires
For communication with a building management system or TOP VISION supervision system, use
serial link RS485.

UPS/NTA GB/ITS16.F page 14
OPERATION
11. OPERATING PRINCIPLE
In normal operating conditions, the IT-SWITCH supplies the load from the preferred source. The latter can be
selected by the operator, depending on the operating requirements of the site.
Two different transfer modes can be selected:
- the manual mode by pressing the push button on the control panel:
¾" SOURCE 1" to supply the load from source 1
¾" SOURCE 2" to supply the load from source 2
- or the automatic mode, upon source failure.
In such a case, the IT-SWITCH:
-senses a failure on the preferred source and ensures the automatic load transfer to the alternate source,
-senses a failure on the alternate source and ensures the automatic seamless load transfer to the priority
source, following a manual transfer to the alternate source.
NOTE: the preferred source (source 1 or source 2) is selected from the control panel (see § 12.2) of from the
TOP VISION supervision workstation.
SECTION
3

UPS/NTA GB/ITS16.F page 15
12. CONTROL PANEL
It comprises a mimic panel that represents the IT-SWITCH and the flow of energy that passes through it.
Three keys are for operating the system.
12.1. Description of states and alarms
1
2
1
2
1
2
12
1
GREEN
led
SOURCE 1 PREFERRED
2
GREEN
led
SOURCE 2 PREFERRED
GREEN
led
INPUT VOLTAGE PRESENT ON SOURCE 1 or SOURCE 2
GREEN
led
SOURCE 1 or SOURCE 2 ON
1
2
1
2
ORANGE led TRANSFER BLOCKED (see § 12.3.3.)
ORANGE led TRANSFER IMPOSSIBLE (see § 12.3.1.)
RED
led
Slow blinking: short-circuit current detected
Rapid blinking: IMMINENT SHUTDOWN (see § 14.2.)
Fixed light on: MANUAL BYPASS switch in position 1 or 2
ORANGE
led
MANUAL BYPASS of source 1 or source 2 ON (IT-SWITCH model E)
Not used (IT-SWITCH models S and B)
ORANGE
led
GENERAL ALARM

UPS/NTA GB/ITS16.F page 16
12.2. Key controls
Key cmakes it possible to close static switch SW1.
Key dmakes it possible to close static switch SW2.
Key
(alarm reset) shows three functions:
- 1 light pressing for resetting the audible beep,
- 1 long pressing (5 seconds minimum) for selecting the preferred source.
- 1 pressing together with key cor d(depending on the source supplying energy) causes the load
disconnection (see § 12.3.4).
12.3. OPERATION EXPLANATIONS
The IT-SWITCH provides two main operating modes:
- the manual transfer by the operator either locally or remotely (through the TOPVISION supervision centre)
- the automatic transfer by detection when the voltage of the preferred source exceeds the permitted
values. The transfer is without sources overlapping.
12.3.1. Manual transfer
The operator can control the load transfer from one source to the other by using keys cor don the control
panel.
When pressing any keys, an audible beep is given to indicate that the request has been taken into account.
The manual transfer is seamless.
If synchronisation conditions are not fulfilled after 25 seconds (factory standard setting), an asynchronous
transfer is performed. If the latter is impossible (e.g. input source out of tolerance) the following led lights !
TRANSFER IMPOSSIBLE
Note: The alarm is automatically deleted when normal conditions are restored.
12.3.2. Automatic transfer
The automatic transfer from the preferred source to the alternate one is seamless for the load. It is carried
out if a voltage drop occurs on the preferred source or if the latter fails. When the preferred source is
restored, the IT-SWITCH automatically transfers the load back to this source after 3 seconds.
An automatic transfer from the alternate to the preferred source can also be performed following a manual
transfer request.

UPS/NTA GB/ITS16.F page 17
To ensure safe transfer, the IT-SWITCH constantly monitors if the alternate source is present and within the
tolerances. If not, the transfer function is inhibited and the IT-SWITCH immediately gives the alarm to inform
the operator that no transfer can be performed. In case of short-circuit on the output of one of the loads
supplied, the transfer function is inhibited. This facility is for preventing the short-circuit transmission to the
other path which is therefore left untouched.
IMPORTANT: this functionality is not available on the IT-SWITCH model S
Transfer can either be synchronous or asynchronous depending on the synchronisation of the sources and
on the configuration of the IT-SWITCH.
¾ Synchronous transfer
The synchronous transfer is automatic when both sources S1 and S2 fulfil synchronisation conditions, that
are when the phase shift is within the values admitted (in standard +/- 15°). In such case, the source
switching does not cause changes of phase. If the phase shift exceeds the values admitted, the synchronous
automatic transfer to the other source is inhibited, unless the system is set with the synchronous and
asynchronous conditions (software configuration).
NOTE: The IT-SWITCH is set in standard for synchronous and asynchronous type transfers. It can however
be set for synchronous transfers only if the load connected is sensible to phase changes. Most information
processing equipment, servers, computers and so on, are not sensible to significant changes of phase.
IMPORTANT: the IT-SWITCH model S can not be set for synchronous transfer only.
¾ Asynchronous transfer
The automatic asynchronous transfer is only executed if the software setting has been validated (standard
factory setting) and if sources S1 and S2 are not synchronised (phase shift exceeding the admitted values).
In such a case, the source switching can show a significant change of phase.
This type of transfer is for safe load switching between sources that are not constantly monitored or
exceptionally out of phase.
12.3.3. Transfer blocked
In the event of five consecutive automatic transfers within 2 minutes (120 seconds), the alarm
1
2(or the
alarm: 2
1
10 ) is given. At this stage, the transfer is blocked and the load is supplied by the alternate source.
Note: to activate the transfer, press key cor ddepending on the source preferred.
IMPORTANT: the IT-SWITCH model S has no "transfer blocked" configuration

UPS/NTA GB/ITS16.F page 18
12.3.4. Load disconnection
The load disconnection control is for load switching off, while sources 1 and 2 are present on the IT-SWITCH.
The control key is
:"alarm reset" (see §12.2).
12.3.5. Overload conditions
As soon as the IT-SWITCH is overloaded (load rate > 103%) the general alarm is given. For currents and
overload permitted values, please refer to § 3.
¾Operation on the preferred source:
A request for transfer to the alternate source can be performed when the overload is half the nominal
overload capacity. Two cases can arise:
- if the transfer can be achieved, the load is transferred to the alternate source,
-if the transfer is impossible, the IT-SWITCH gives the "imminent shutdown" alarm. When the maximum
overload capacity is reached, the load is disconnected.
¾Operation on the alternate source:
In case of overload, the "imminent shutdown" alarm is given. When the maximum overload capacity is
reached, the load is disconnected by the IT-SWITCH.
¾ Principle of the automatic start up:
In case both sources fail while the IT-SWITCH is supplied by one or the other source, the unit resumes
operation with the first one to be restored.
The transfer to the preferred source is automatic when the latter is restored.
The automatic start-up function can be configured and is activated by default.

UPS/NTA GB/ITS16.F page 19
13. COMMISSIONNING - OPERATION
13.1. Preliminary checks
Only initiate commissioning after completing:
- earth bonding,
- adequate connections of the IEC sockets (or connections to terminals).
13.2. Safety - Reminders
CAUTION
Even when switched off, the IT-SWITCH is constantly live, supply voltage is
present at the input of source 1 and 2.
ADVICE
Any loose item is secured.
Do carefully follow the using or maintenance instructions described in the manual.
13.3. Preliminary conditions
Source 1 and Source 2 are live.
13.4. Load supply
From the control panel, press key:
c, for the load to be supplied by source 1, or
d, for the load to be supplied by source 2.
If the operator selects the alternate source, the IT-SWITCH supplies the load from the source selected.
However, the IT-SWITCH automatically switches the load to the preferred source after a few seconds.
13.5. Changing the source priority (models S, B and E)
NOTE:By default, source 1 is preferred when switching on the unit.
Press key for 5 seconds, and make sure that the led lights confirm the change
of source.
After changing the source priority, the load is automatically transferred, after a few seconds, to the newly
preferred source.