BOCK HGX34/110-4 ML CO2 T User manual

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HGX  T
BOCK HGX34 CO2T

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
BOCK®

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About these instructions
Manufacturer
Contact
1 Safety 4
1.1 Identication of safety instructions
1.2 Qualications required of personnel
1.3 Safety instructions
1.4 Intended use
2 Product description 6
2.1 Short description
2.2 Name plate
2.3 Type key
Read these instructions before assembly and before using the compressor. This will avoid misunder-
standings and prevent damage. Improper assembly and use of the compressor can result in serious
or fatal injury.
Observe the safety instructions contained in these instructions.
These instructions must be passed onto the end customer along with the unit in which the compres-
sor is installed.
Contents Page
Bock GmbH
72636 Frickenhausen
Bock GmbH
Benzstraße 7
72636 Frickenhausen
Germany
Telephone [phone]
Fax [phone]
www.bock.de
[email protected]

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Contents Page
3 Areas of application 8
3.1 Refrigerants
3.2 Oil charge
3.3 Limits of application
4 Compressor assembly 9
4.1 Storage and transportation
4.2 Setting up
4.3 Connecting the pipelines - solder system
4.4 Connecting the pipelines - cutting ring system
4.5 Pipes
4.6 Flange shut-off valves (HP/LP)
4.7 Laying suction and pressure lines
4.8 Operating the shut-off valves
4.9 Operating mode of the lockable service connections
4.10 Oil return
4.11 Suction pipe lter
5 Electrical connection 14
5.1 Information for contactor and motor contactor selection
5.2 Standard motor, designed for direct or part winding start
5.3 Basic circuit diagram for part winding start
5.4 Special motor: design for direct or star-delta start
5.5 Basic circuit diagram for star-delta start with special motor
5.6 Electronic trigger unit INT69 G
5.7 Connection of the electronic trigger unit INT69 G
5.8 Functional test of the electronic trigger unit INT69 G
5.9 Oil sump heater
6 Commissioning 24
6.1 Preparations for start-up
6.2 Pressure strength test
6.3 Leak test
6.4 Evacuation
6.5 Refrigerant charge
6.6 Start-up
6.7 Pressure switch
6.8 Decompression valves
6.9 Avoiding slugging
6.10 Filter dryer
7 Maintenance 28
7.1 Preparation
7.2 Work to be carried out
7.3 Spare parts recommendation / accessories
7.4 Lubricants
7.5 Decommissioning
8 Technical data 30
9 Dimensions and connections 32
10 Declaration of incorporation 34
11 Service 35

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1.1 Identication of safety instructions:
1.2 Qualications required of personnel
WARNING Inadequately qualied personnel poses the risk of accidents, the
consequence being serious or fatal injury. Work on compressors
must therefore only be performed by personnel with the
qualications listed below:
• For example, a refrigeration technician, refrigeration mechatronics
engineer. As well as professions with comparable training, which
enable personnel to assemble, install, maintain and repair refrigeration
and air-conditioning systems. Personnel must be capable of assessing
the work to be carried out and recognising any potential dangers.
DANGER Indicates a dangerous situation which, if not avoided, will cause
immediate fatal or serious injury
WARNING Indicates a dangerous situation which, if not avoided, may cause
fatal or serious injury
CAUTION Indicates a dangerous situation which, if not avoided, may imme-
diately cause fairly severe or minor injury.
ATTENTION Indicates a situation which, if not avoided, may cause property
damage
INFO Important information or tips on simplifying work
1|Safety

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These assembly instructions describe the standard version of the compressors named in the ti-
tle manufactured by Bock. Bock refrigerating compressors are intended for installing in a
machine (within the EU according to the EU Directives 2006/42/EC Machinery Directive and
2014/68/EU Pressure Equipment Directive).
Commissioning is only permissible if the compressors have been installed in accordance with these
assembly instructions and the entire system into which they are integrated has been inspected and
approved in accordance with legal regulations.
The compressors are intended for use with CO2 in transcritical and/or subcritical systems in compli-
ance with the limits of application.
Only the refrigerant specied in these instructions may be used.
Any other use of the compressor is prohibited!
1.4 Intended use
1.3 Safety instructions
WARNING Risk of accident.
Refrigerating compressors are pressurised machines and therefore
require particular caution and care in handling.
The maximum permissible overpressure must not be exceeded,
even for testing purposes.
Risk of burns!
- Depending on the operating conditions, surface temperatures of
over 60 °C on the pressure side or below 0 °C on the suction side
can be reached.
- Avoid the contact with refrigerant under any circumstances.
The contact with refrigerant can lead to severe burns and skin
irritations.
Danger of suffocation.
CO2 is a nonammable, acidic, colourless and odourless gas and
heavier than air.
Never release signicant volumes of CO2or the entire contents of
the system into closed rooms!
Safety installations are designed or adjusted in accordance with EN
378-2 or appropriate safety standards.
• Transcritical CO2applications are still in the development phase.
• They require a completely new kind of system and control.
• They are not a general solution for the substitution of F-gases.
• Therefore, we expressly point out that all information in this
assembly instruction has been provided according to our current
level of knowledge and may change due to further development.
Legal claims based on the correctness of the information cannot
be made at any time and are hereby expressly excluded.
WARNING The compressor may not be used in potentially explosive
environments!
1|Safety

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• Semi-hermetic four-cylinder reciprocating compressor with suction gas cooled driving motor.
• The ow of refrigerant sucked in from the evaporator is led over the engine and provides for a
particularly intensive cooling. Thus the engine can be kept on a relatively low temperature level
specially during high load.
• Oil pump independent of direction of rotation for reliable and safe oil supply.
• One decompression valve each on the low and high pressure side, which vent into the atmos-
phere when inadmissibly high pressure levels are reached.
Fig. 1
2.1 Short description
Fig. 2
Oil sight glass
Valve plate
Cylinder cover
Dimension and connection values can be found in chapter 9
Transport eyelet
Oil pump
Discharge
shut-off valve
Name plate
Suction
shut-off valve
Terminal box
2|Product description

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/
HG 34290-4CO2 X
2.3 Type key (example)
¹) HG - Hermetic Gas-Cooled (suction gas-cooled)
²) X - Ester oil charge
³) ML - Normal cooling and deep freezing at low and medium evaporation temperatures
S - For frequency regulation and extended limits of application
SH - For high evaporating temperatures eg. heat pumps, different oil charge
Transcritical
CO2 version
Compressor version ³)
Number of poles
Swept volume
Number of cylinders
Size
Oil charge ²)
Series ¹)
T
S
1
2
3
4
5
6
7
8
9
10
11
12
13
BC12345-001
59,8 A
170 A 275 A
20,1
24,1
CO2,C 85 E
HGX34/230-4 S CO2T
1 Type designation
2 Machine number
3 Maximum operating current
4 Starting current (rotor blocked)
Y: Part winding 1
YY: Part winding 1 and 2
5 ND (LP): max. permissible operating
pressure (g) Low pressure side
HD (HP): max. permissible operating
pressur e (g) High pressure side
Observe the limits of
application diagrams!
50 Hz
60 Hz
6 Voltage, circuit, frequency
7 Nominal rotation speed
8 Displacement
9 Voltage, circuit, frequency
10 Nominal rotation speed
11 Displacement
12 Oil type lled at the factory
13 Terminal box protection type
Electrical accessories can change
the IP protection class!
}
}
Fig. 3
100/150 bar
Bock GmbH, Benzstraße 7
72636 Frickenhausen, Germany
2.2 Name plate (example)
2|Product description
BOCK

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The compressors are lled at the factory with the following oil type:
Compressor version ML and S: Bock C85E
Compressor version SH: Bock C150E
(only this oils may be used)
3.1 Refrigerants
• CO2: R744 (Recommendation CO2 quality 4.5 (< 5 ppm H2O))
3.2 Oil charge
ATTENTION Compressor operation is possible within the operating limits
shown in the diagrams. Please note the signicance of the
shaded areas. Thresholds should not be selected as design or
continuous operation points.
- Permissible ambient temperature (-20 °C) - (+60 °C).
- Max. permissible discharge end temperature 160 °C.
- Min. discharge end temperature ≥50 °C.
- Min. oil temperature ≥ 30 °C.
- Max. permissible switching frequency 12x /h.
- A minimum running time of 3 min. steady-state condition
(continuous operation) must be achieved.
Avoid continuous operation in limit range.
For operation with frequency converter:
- Frequency range 20 - 70 Hz.
- The maximum current and power consumption must not be
exceeded. In the case of operation above the mains frequency,
the application limit can therefore be limited.
3.3 Limits of application
ATTENTION Property damage possible.
The oil level must be in the
visible part of the sight glass;
damage to the compressor
is possible if overfilled or
underfilled! Fig. 4
Max.
Min.
0.9 Ltr.
Oil level ~
~
3|Areas of application
Maximum permissible operating
pressure (LP/HP)1): 100/150 bar
1) LP = Low pressure HP = High pressure

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4|Compressor assembly
INFO New compressors are factory-lled with inert gas. Leave this
service charge in the compressor for as long as possible and prevent
the ingress of air.
Immediately after refrigeration technological connection of
the compressor close the shut-off devices in suction-, dis-
charge-, oil return line etc. and evacuate the compressor.
Check the compressor for transport damage before starting any
work.
4.2 Setting up
Setup on an even surface or frame with sufcient load-bearing
capacity.
Single compressor preferably on vibration damper.
Compound connection basically rigid.
Provide adequate clearance for maintenance work.
Ensure adequate compressor ventilation.
Do not use in a corrosive, dusty, damp atmosphere or a com-
bustible environment.
F
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B
A
1 2
3
4
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C
4
3
2
1
A
B
Tol.-Ang. DIN ISO 2768-mK
Ra Rz
Maß Passung
Freigabe
Alternativbezug:
Baumustergeprüft
Teil inaktiv
Lieferantenzeichnung
-
-
K.-Auftrag:
PL:
Zeichnung ungültig
Entwicklungsstand
Teil keine Serie
120
400
±0.5
über 0.5
bis 6
Benzstraße 7 - 72636 Frickenhausen - Germany - www.bock.de
-
-
Unbemaßte Radien:
-
Diese Zeichnung ist unser Eigentum!
Sie darf ohne unsere Genehmigung weder nach-
gebildet, vervielfältigt, oder Dritten Personen zu-
gänglich gemacht werden. Der Nachbau nach
dieser Zeichnung, oder an Hand der nach dieser
Zeichnung hergestellten Gegenstände durch den
Abnehmer oder Dritte ist nicht gestattet.
Wir behalten uns alle Rechte, gemäß DIN ISO 16016
an dieser Zeichnung vor.
Bearb.
Datum
Änderungs-Nr.
Werkstoff:
Ausgangsteil, bzw. Rohteil:
--
Gepr.
Name Datum
19.04.
Werkstückkanten
DIN ISO 13715
Ersatz für:
Ersetzt durch:
Erstellt
2010
Geprüft
-
Kurz
Zone
1/x
Oberflächenbehandlung / Härte:
-
Blatt:
Änderungsbeschreibung
400
Benennung:
±0.8
1000
30 6
-
±0.3
120
30
±0.2
Zeichn.-Nr. Teile-Nr.
Oberflächenangaben ISO 1302
x.xxxx-xxxxx.x
Zust.
Gußtoleranzen:
Gewicht: (kg)
±0.1
Maßstab:
1:1
Wasserwaage
für Indesign
Der Lieferant muß sicherstellen, dass die Ware in
einwandfreiem Zustand angeliefert wird (Korrosions-
schutz, Verpackung für sicheren Transport).
Rz 25
Rz 160
s
25
z y x w u t
0,05
Rz 1,6
0,3
0,7
1,6
2
Rz 16
6,3
Rz 63
Rz 6,3
Rz 12,5
F:\user\kurz\3D Sachen\3D Teile\Zeichnungen\Wasserwaage
?
4.1 Storage and transportation
Use transport eyelet.
Do not lift manually!
Use lifting gear!
Storage at (-30 °C) - (+70 °C), maximum permissible relative humidity
10 % - 95 %, no condensation.
Do not store in a corrosive, dusty, vaporous atmosphere or in a com-
bustible environment.
ATTENTION Attachments (e.g. pipe holders, additional units, fastening parts,
etc.) directly to the compressor are not permissible!

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Material soldering / welding connection: S235 (JRG2C)
The pipe connections have graduated inside diameters so that pipes with
standard millimetre and inch dimensions can be used.
The connection diameters of the shut-off valves are rated for maximum
compressor output. The actual required pipe cross section must be
matched to the output. The same applies for non-return valves.
Fig. 5: graduated
internal diameter
4.3 Connecting the pipelines - solder system
ATTENTION Damage possible.
Superheating can damage the valve.
Remove the pipe supports therefore from the valve for soldering
and accordingly cool the valve body during and after soldering.
Only solder using inert gas to inhibit oxidation products (scale).
• On its high-pressure side, the compressor has a shut-off valve with multi-sided cutting ring for safe
installation of the discharge line.
Cutting ring function after tightening the union nut
. . . . .
4.4 Connecting the pipelines - cutting ring system
Fig. 6
Figure similar
Tube preparation:
The tube has to be sawn in a right angle. An angular tolerance of ± 1° is permissible.
Slightly trim the pipe ends inside and outside. For thin walled steel pipes or soft pipes made of
nonferrous metal, reinforcing sleeves have to be used.
Pipe assembly:
Push union nut (5) and cutting ring (3) onto pipe (2). Insert pipe into socket (6) as far as it will go and
firmly press against pipe stop, otherwise incorrect assembly. Hand tighten union nut until socket,
cutting ring and union nut are locked. Tighten union nut 1 1/2 turns using a spanner wrench. The
cutting ring is noticeably locked to the socket face (for assembly inside pipe connection, hold up
valve with a spanner wrench). This should cause the cutting ring with its cutting edges (1) to cut into
the pipe resulting in a visible collar. In order to stick to the turns we recommend using marking lines
on union nut and pipe. After assembly, it is necessary to check the collar. The gasket must not be
damaged. At least 80 % of the cutting face has to be covered. After check-up, screw on and tighten
again as described above.
Collar
4|Compressor assembly

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4|Compressor assembly
4.5 Pipes
4.6 Flange shut-off valves (HP/LP)
CAUTION Risk of injury.
The compressor must be depressurized through connections A
and B before commencing any work and prior to connecting to the
refrigerant system.
AB
Pipes and system components must be clean and dry inside and free of scale, swarf and layers of
rust and phosphate. Only use hermetically sealed parts.
Lay pipes correctly. Suitable vibration compensators must be provided to prevent pipes being
cracked and broken by severe vibrations.
Ensure a proper oil return.
Keep pressure losses to an absolute minimum.
Fig. 7 Fig. 8

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4.8 Operating the shut-off valves
Before opening or closing the shut-off valve, release the valve spindle seal by approx. 1/4 of a turn
counter-clockwise.
After activating the shut-off valve, re-tighten the adjustable valve spindle seal clockwise.
Fig. 10 Fig. 11
Valve spindle seal
Release Tighten
4.7 Laying suction and pressure lines
A rule of thumb: Always lay the rst pipe section starting from the shut-off valve downwards and
parallel to the drive shaft.
ATTENTION Property damage possible.
Improperly installed pipes can cause cracks and tears which can
result in a loss of refrigerant.
INFO Proper layout of the suction and pressure lines directly after
the compressor is integral to the smooth running and vibration
behaviour of the system.
Fig. 9
Rigid fixed
point
As short as
possible
4|Compressor assembly

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4|Compressor assembly
To ensure the oil return function will work reliably no matter what kind of system conguration you
are using, Bock recommends incorporating oil separators or oil level monitoring equipment. The "O"
connection is already available from the factory for the purpose of installing the additional oil level
monitoring component. Oil should be returned from the oil separator to the compressor via the "D1"
connection provided for this purpose on the compressor.
For systems with long pipes and higher degree of contamination, a lter on the
suction-side is recommended. The lter has to be be renewed depending on the degree of contamina-
tion (reduced pressure loss).
4.10 Oil return
4.11 Suction pipe lter
Pipe connection
Pipe connection
4.9 Operating mode of the lockable service connections
Fig. 12
Opening the shut-off valve:
Spindle: turn to the left (counter-clockwise) as far as it will go.
—> Shut-off valve completely opened / service connection closed.
The connection which cannot be shut off is intended for safety devices.
Fig. 13
Opening the service connection
Spindle: Turn 1/2 - 1 turn to the right clockwise.
—> Service connection opened / shut-off valve opened.
The connection which cannot be shut off is intended for safety devices.
Service connec-
tion closed
Connection
blocked
Spindle
Connection cannot
be shut off
Service connec-
tion opened
Spindle Connection
open
Compressor
Compressor
After activating the spindle, generally t the spindle protection cap again and tighten with 40 - 50 Nm.
This serves as a second sealing feature during operation.
Connection cannot
be shut off

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5.1 Information for contactor and motor contactor selection
5 Electrical connection
INFO Connect the compressor motor in accordance with the circuit diagram
(see inside of terminal box).
Use suitable cable glands of the correct protection type (see name
plate) for routing cables into the terminal box. Insert the strain reliefs
and prevent chafe marks on the cables.
Compare the voltage and frequency values with the data for the
mains power supply.
Only connect the motor if these values are the same.
DANGER Risk of electric shock! High voltage!
Only carry out work when the electrical system is disconnected
from the power supply!
All protection equipment, switching and monitoring devices must comply with the local safety reg-
ulations and established specications (e.g. VDE) as well as the manufacturer’s specications.
Motor protection switches are required! Motor contactors, feed lines, fuses and motor protec-
tion switches must be rated according to the maximum operating current (see name plate). For
motor protection, use a current-dependent, time-delayed overload protection device for monitoring
all three phases. Adjust the overload protection device so that it must be actuated within 2 hours at
1.2 times the maximum working current.
ATTENTION When attaching accessories with an electrical cable, a minimum
bending radius of 3 x the cable diameter must be maintained for
laying the cable.
5|Electrical connection

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5|Electrical connection
5.2 Standard motor, designed for direct or part winding start
Designation on the name plate
Y/YY
Compressors marked in this way are suitable for direct or part winding start. The motor winding is
divided into two parts: part winding 1 = 50 % and part winding 2 = 50 %. This winding division reduces
the start-up current during a part winding start to approx. 50 % of the value for a direct start.
In the factory, the motor is switched for direct starting (YY). For part winding start (Y/YY), remove the
bridges and connect the motor feed cable according to the circuit diagram:
400 V
Direct start YY Part winding start Y/YY
L1
L2
L3
L1
L2
L3
L1 L3
L2
PTC
PW II
PW I
PTC
ATTENTION Property damage possible.
Failure to comply results in reversed elds of rotation and can cause
motor damage. After the motor has started up with part winding 1,
part winding 2 must be switched on after max. 1 second delay. Fail-
ure to comply can be detrimental to the service life of the motor.
Ensure that power is supplied via QA2 to winding 1 (50 %)
(1U1 / 1V1 / 1W1) and via QA3 to winding 2 (50 %) (2U1 / 2V1 / 2W1).
The motor contactors (QA2 / QA3) are each to be rated for approx.
50 % of the max. operating current.

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5.3 Basic circuit diagram for part winding start
* With several connect them in series
Fig. 14
Οnderung
2
0
Datum Name
Datum
Bearb.
Gepr.
Norm
1
20.02.2009
bauknecht
26.11.2020
Urspr.
2
Ers. f.
3
Ers. d.
4
PW INT69 HG44/66
567
BOCK COMPRESSORS
8
=
+
9
Bl.
6.d Bl.
5.a
2.a
Anschlußkasten Verdichter
BT1
INT69
DELTA- P II
QA1
L1 L2 L3 N PE
FC1.1
I> I> I>
QA2
1U1
1V1
1W1
PE
EC1
M
Y/YY
2U1
2V1
2W1
FC1.2
I> I> I>
QA3
FC1.1
FC1.2
FC2
SF1
BP2
P>
QA2
BP3
P
QA2
KF1
KF1
QA2
L1.1
L2.1
L3.1
L1.2
N
PE
QA3
BT4
BT2
Θ
1112 14
L N B1 B2
12
11
10
9
8
7
6
5
4
3
2
1
Θ
vio bn bu gr
Θ
EB1
pk og
21
20
BT3
Θ
50% 50%
Compressor terminal box
BP2 High pressure safety monitor
BP3 Safety chain (high/low pressure monitoring)
BT1 Cold conductor (PTC sensor) motor winding
BT2 Thermal protection thermostat*
BT3 Oil temperature sensor
BT4 Release switch (thermostat)
DELTA-P II Oil differential pressure sensor DELTA-P II (accessory)
EB1 Oil sump heater
EC1 Compressor motor

D
GB
F
E
17
96459-01.2021-DGb
FC1.1/1.2 Motor protection switch
FC2 Control power circuit fuse
INT69 G Electronic trigger unit INT69 G
KF1 Delay relay for contactor switch over
QA1 Main switch
QA2 Mains contactor (part winding 1)
QA3 Mains contactor (part winding 2)
SF1 Control voltage switch
Οnderung
2
0
Datum Name
Datum
Bearb.
Gepr.
Norm
1
20.02.2009
bauknecht
26.11.2020
Urspr.
2
Ers. f.
3
Ers. d.
4
PW INT69 HG44/66
567
BOCK COMPRESSORS
8
=
+
9
Bl.
6.d Bl.
5.a
2.a
Anschlußkasten Verdichter
BT1
INT69
DELTA- P II
QA1
L1 L2 L3 N PE
FC1.1
I> I> I>
QA2
1U1
1V1
1W1
PE
EC1
M
Y/YY
2U1
2V1
2W1
FC1.2
I> I> I>
QA3
FC1.1
FC1.2
FC2
SF1
BP2
P>
QA2
BP3
P
QA2
KF1
KF1
QA2
L1.1
L2.1
L3.1
L1.2
N
PE
QA3
BT4
BT2
Θ
1112 14
L N B1 B2
12
11
10
9
8
7
6
5
4
3
2
1
Θ
vio bn bu gr
Θ
EB1
pk og
21
20
BT3
Θ

18
D
GB
F
E
96459-01.2021-DGb
5.4 Special motor: design for direct or star-delta start
Designation on the name plate
∆/ Y
5|Electrical connection

D
GB
F
E
19
96459-01.2021-DGb
Star-delta start-up is only possible for 230 V power supply. Example:
400 V Y
Direct start only
L1 L3
L2
PTC
230 V Δ
Direct start Star-delta start
L1
L2
L3
L1
L2
L3
L1 L3
L2
PTC PTC
W2
U2
V2
W1
U1
V1
W2
U2
V2
W1
U1
V1
5|Electrical connection

20
D
GB
F
E
96459-01.2021-DGb
5.5 Basic circuit diagram for star-delta start with special motor
* With several connect them in series
Fig. 15
Οnderung
4
0
Datum Name
Datum
Bearb.
Gepr.
Norm
1
20.02.2009
bauknecht
03.11.2020
Urspr.
2
Ers. f.
3
Ers. d.
4
D/S INT69 HG44/66 neu
567
BOCK COMPRESSORS
8
=
+
9
Bl.
6.d Bl.
6.b
6.a
Anschlußkasten Verdichter
BT1
INT69G
DELTA- P II
QA1
L1 L2 L3 N PE
U1
V1
W1
PE
U2
V2
W2
FC1.1
FC1.2
FC2
SF1
BP2
P>
BP3
P
QA2
L1.1
L2.1
L3.1
L1.2
N
PE
BT4
BT2
Θ
1112 14
L N B1 B2
12
11
10
9
8
7
6
5
4
3
2
1
Θ
vio bn bu gr pk og
Θ
EB1
FC1.1
I> I> I>
1
2
QA2
FC1.2
I> I> I>
3
4
5
6
1
2
QA4
Y
3
4
5
6
1
2
QA3
D
3
4
5
6
EC1
M
3˜
QA2
QA2
QA4 KF1
QA4
QA3
KF1
QA3
QA4 KF1
20
21
BT3
Θ
Compressor terminal box
BP2 High pressure safety monitor
BP3 Safety chain (high/low pressure monitoring)
BT1 Cold conductor (PTC sensor) motor winding
BT2 Thermal protection thermostat (PTC sensor)*
BT3 Oil temperature sensor
BT4 Release switch (thermostat)
DELTA PII Oil differential pressure sensor DELTA-P II (accessory)
EB1 Oil sump heater
EC1 Compressor motor