Danfoss BOCK HG4 User manual

AQ452034894212en-000201
HG4/310-4 HG4/310-4S HGX4/310-4 HGX4/310-4S
HG4/385-4 HG4/385-4S HGX4/385-4 HGX4/385-4S
HG4/465-4 HG4/465-4S HGX4/465-4 HGX4/465-4S
HG4/555-4 HG4/555-4S HGX4/555-4 HGX4/555-4S
HG4/650-4 HG4/650-4S HGX4/650-4 HGX4/650-4S
BOCK®HG4
Operating guide
BockGmbH, Benzstr. 7
72636Frickenhausen, Germany
BOCK
Translation of the original instructions

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About these instructions
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.

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Contents Page
1 Safety 4
 1.1 Identicationofsafetyinstructions
 1.2 Qualicationsrequiredofpersonnel
1.3 General safety instructions
1.4 Intended use
2 Product description 6
2.1 Short description
2.2 Name plate
2.3 Type key
3 Areas of application 8
3.1 Refrigerants
3.2 Oil charge
3.3 Limits of application
4Compressor assembly 10
4.1 Storage and transport
4.2 Setting up
4.3 Pipe connections
4.4 Pipes
4.5 Laying suction and pressure lines
4.6 Operating the shut-off valves
4.7 Operating mode of the lockable service connections
5 Electrical connection 13
5.1 Information for contactor and motor contactor selection
5.2 Standard motor, design for direct or part winding start
5.3 Basic circuit diagram for part winding start with standard motor
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 MP 10
5.7 Connecting the trigger unit MP 10
5.8 Functional test of the trigger unit MP 10
5.9 Oil sump heater (accessories)
6 Commissioning 23
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 Avoiding slugging
6.8 Connection of oil level regulator
7 Maintenance 25
7.1 Preparation
7.2 Work to be carried out
7.3 Spare parts recommendation/accessories
7.4 Lubricants / oil
7.5 Decommissioning
8 Technical data 27
9 Dimensions and connections 28
10 Declaration of incorporation 30

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1|Safety
1.2 Qualicationsrequiredofpersonnel
1.3 General safety instructions
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ca-
tions listed below:
• For example, a refrigeration technician, refrigeration mechatron-
ics 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
thework to be carried out and recognising any potential dangers.
WARNING! • Refrigerating compressors are pressurised machines and
thereforerequireparticularcautionandcareinhandling.
• 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.
• Themaximumpermissibleoverpressuremustnotbeexceeded,
even for testing purposes.
1.1 Identicationofsafetyinstructions:
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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.

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1|Safety
These assembly instructions describe the standard version of the HG4 manufactured by Bock. The
compressor is intended for use in refrigeration systems in compliance with the limits of application.
Onlytherefrigerantspeciedintheseinstructionsmaybeused.
Any other use of the compressor is prohibited!
The Bock refrigerating compressor named in the title is 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 compressor has been installed in accordance with these
assembly instructions and the entire system into which it is integrated has been inspected and
approved in accordance with legal regulations.
1.4 Intended use
WARNING! The compressor may not be used in potentially
explosive environments!

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2|Product description
• Semi-hermetic four-cylinder reciprocating compressor with suction-gas cooled drive motor.
• Flange-mounted drive motor on the compressor case.
• Preferred application range: normal refrigerating and air-conditioning.
2.1 Short description
Dimension and connection values can be found in Chapter 9
Name plate
Fig. 1
Valve plate
Cylinder cover
Terminal box
Transport eyelet
Discharge
shut-off valve
Oil pump
Suction shut-
off valve
Oil sight glass
Drive section
Motor section
BockGmbH, Benzstr. 7
72636Frickenhausen, Germany
BOCK

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1
2
3
4
5
6
7
8
9
10
11
12
13
AS35830A006
HGX4/310-4
17,0A
57 A 75 A
27,1
32,5
SE 55
2|Product description
Fig. 2
2.3 Typekey(example)
¹) HG - Hermetic Gas-cooled (suction gas-cooled)
²) X - Ester oil charge (HFC refrigerant, e.g. R134a, R404A/R507, R407C)
3) S - More powerful motor, e.g. for air-conditioning applications
Motor variant 3)
Number of poles
Swept volume
Size
Oil charge ²)
Series ¹)
1 Typedesignation 6 Voltage,circuit,frequency
2 Machine number 7 Nominal rotation speed
3 maximum operating current 8 Displacement
4 Startingcurrent(rotorblocked) 9 Voltage,circuit,frequency
Y: Part winding 1 10 Nominal rotation speed
YY: Part windings 1 and 2 11 Displacement
5 ND (LP): max. admissible operating  12 Oiltypelledatthefactory
pressur e (g) Low pressure side 13 Terminal box protection type
HD (HP): max. admissible operating Electrical accessories can change
pressur e(g) High pressure side the IP protection class!
Observe the limits of application
diagrams!
50 Hz
}
60 Hz
}
/
HG 4650-4 XS
2.2 Name plate(example)
Bock GmbH, Benzstr. 7
72636 Frickenhausen, Germany
BOCK
BOCK lub E55

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3|Areas of application
ATTENTION! Compressor operation is possible within the operating limits.
These can be found in Bock compressor selection tool (VAP)
undervap.bock.de.Observetheinformationgiventhere.
-Permissibleambienttemperature(-20°C)-(+60°C)
- Max. permissible discharge end temperature 140 °C
    -Max.permissibleswitchingfrequency12x/h.
- A minimum running time of 3 min. steady-state condition
(continuousoperation)mustbeachieved.
For operation with supplementary cooling:
- Use only oils with high thermal stability.
- Avoid continuous operation near the threshold.
For operation with capacity regulator:
- Continuousoperation,whenthecapacityregulatorisactivated,
is not permissible and can cause damage to the compressor.
- The suction gas superheat temperature may need to be reduced
or set individually when operating near to the threshold.
- When the capacity regulator is activated, the gas velocity in
the system can not under certain circumstances ensure that
sufcientoilistransportedbacktothecompressor.
Foroperationwithfrequencyconverter:
- 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.
When operating in the vacuum range, there is a danger of air
enteringonthesuctionside.Thiscancausechemicalreactions,
a pressure rise in the condenser and an elevated compressed-gas
temperature. Prevent the ingress of air at all costs!
 Thecompressorsarelledatthefactorywiththefollowingoiltype:
- for R134a, R404A/R507, R407C BOCK lub E55
- for R22 BOCK lub A46
Compressors with ester oil charge (BOCK lub E55) are marked with an X in the type
designation (e.g. HGX4/650-4).
3.2 Oil charge
3.3 Limits of application
INFO! Forrefilling,werecommendtheaboveoiltypes.
Alternatives: see chapter 7.4
The oil level must be in the
visible part of the sight
glass; damage to the com-
pressor is possible if over-
filled or underfilled!
ATTENTION!max.
min.
1,8 Ltr.
oil level
Fig. 3
~
~
3.1 Refrigerants
• HFKW / HFC: R134a, R404A/R507, R407C • (H)FCKW / (H)CFC: R22

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Evaporation temperature (°C)
Condensing temperature (°C)
Suction gas superheat (K)
Suction gas temperature (°C)
3|Areas of application
Design for other
areasonrequest
R134a
R407C
R404A/R507
R22
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Unlimited application range
Supplementary cooling or
reduced suction gas temperature
Supplementary cooling and
reduced suction gas temperature
Motor version S
(more powerful motor)
Max. permissible operating
pressure(LP/HP)1): 19/28 bar
1) LP = Low pressure
HP = High pressure

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4|Compressor assembly
 Setuponanevensurfaceorframewithsufcientload-
bearing capacity.
Single compressor preferably on vibration damper.
Duplex and parallel circuits always rigid.
 Provideadequateclearanceformaintenancework.
 Ensureadequatecompressorventilation.
Do not use in a corrosive, dusty, damp atmosphere or a
combustible environment.
Fig. 10
Fig. 11
Fig. 12
ATTENTION! Superheating can damage the valve.
Remove the pipe supports from the valve for soldering.
 Onlysolderusinginertgastoinhibitoxidationproducts(scale).
4.3 Pipe connections
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.
  Check the compressor for transport damage before starting any
 work.
4.2 Setting up
?
4.1 Storage and transport
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.
Fig. 9
Fig. 8
ATTENTION! Attachments(e.g.pipeholders,additionalunits,fasteningparts,
etc.)directlytothecompressorarenotpermissible!

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4.5 Laying suction and pressure lines
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.
ATTENTION! Improperlyinstalledpipescancausecracksandtearswhichcan
resultinalossofrefrigerant,
A rule of thumb:
Alwayslaytherstpipesectionstartingfromtheshut-offvalvedownwards and
parallel to the drive shaft.
4|Compressor assembly
4.4 Pipes
Pipes and system components must be clean and dry inside and free of scale, swarf and layers of
rust and phosphate. Only use air-tight 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.
The pipe connections have graduated inside diameters so that pipes with
standart 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. 13: graduated
internal diameter
Fig. 14
Rigid
fixed point
As short as
possible
BockGmbH,Benzstr.7
72636Frickenhausen,Germany
BOCK
BockGmbH,Benzstr.7
72636Frickenhausen,Germany
BOCK

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4|Compressor assembly
4.6 Operating the shut-off valves
Before opening or closing the shut-off valve, release the valve spindle seal by approx. ¼ of a turn
counter-clockwise.
After activating the shut-off valve, re-tighten the adjustable valve spindle seal clockwise.
Pipe connection
Pipe connection
4.7 Operatingmodeofthelockableserviceconnections
Fig. 17
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. 18
Opening the service connection
Spindle: Turn ½ - 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
Connection cannot be
shut off
Service connec-
tion opened
Spindle Connection
open
Compressor
Compressor
Fig. 15 Fig. 16
Valvespindleseal
Release
Tighten
Afteractivatingthespindle,generallytthespindleprotectioncapagainandtightenwith14-16Nm.
This serves as a second sealing feature during operation.

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5|Electrical connection
5 Electrical connection
  DANGER! Highvoltage!Riskofelectricshock!Onlycarryoutworkwhenthe
electrical system is disconnected from the power supply!
INFO! Connect the compressor motor in accordance with the circuit diagram
(see inside of terminal box).
Use suitable cable entry point 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.
5.2 Standardmotor,designfordirectorpartwindingstart
Designation on the name plate Sticker on the terminal box
Y/YY
Compressors with this marking are suitable for direct or partial winding start. The motor winding is
subdivided into two parts: Partial winding 1 = 66% and part winding 2 = 33%. This winding division
reduces the start-up current needed for a part winding start to approx. 65% of that for a direct start.
INFO! A mechanical unloaded start with bypass solenoid valve is
 notrequired.
5.1 Information for contactor and motor contactor selection
Allprotectiondevicesandswitchingormonitoringunitsmustbettedinaccordancewiththelocal
safetyregulationsandestablishedspecications(e.g.VDE)aswellaswiththemanufacturer’sinfor-
mation. Motorprotectionswitchesarerequired! Motor contactors, feed lines, fuses and motor
protection switches must be rated on the basis of the maximum working current (see name plate).
For motor protection use a current-dependent and time-delayed overload protection device for moni-
toring all three phases. Set the overload protection device so that it must be actuated within 2 hours,
if there is 1.2 times the max. 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.

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5.3 Basic circuit diagram for part winding start with standard motor
R1 Cold conductor (PTC sensor) motor winding
R2 Thermal protection thermostat (PTC sensor)
F1.1 /1.2 2 motor protection switches (66% / 33% of I Atotal)
F2 Control power circuit fuse
F3 High pressure safety monitor
F4 Safety chain (high/low pressure monitoring)
F5 Oil differential pressure monitor
B1 Release switch (thermostat)
nderung
0
Datum Name
Datum
Bearb.
Gepr.
Norm
1
20.Feb.2009
Kelich
09.M„r.2010
Urspr.
2
Ers.f.
3
Ers.d.
4
PWMP10
5 6 7
BOCKCOMPRESSORS
8
=
+
9
Bl.
1
Bl.
1
XSS
Q1
L1 L2 L3 NPE
AnschluákastenVerdichter
I=66%
F1.1
K1
1
2
1
3
4
2
5
6
3
1U1
1V1
1W1
PE
M
Y/YY
M1
R1
2U1
2V1
2W1
I=33%
F1.2
K2
1
2
4
3
4
5
5
6
6
X1 L1 L1 N N 43 43 11 12 14
LSM
X2123456
7
F1.1
F1.2
8
R2
4A
F2
S1
910
MP10
11
F5
K1
12
T2
13
N
P™l
14
L
15
M
16
S
P>
F3
17 18 19
K1
P
F4
20
K1
K1T
K2
21 22
K1T
P<
B1
23 24
K1
25
E1
26
L1.1
L2.1
L3.1
L1.2
N
PE
Fig. 19 Compressor terminal box

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Q1 Main switch
M1 Compressor motor
K1 Mains contactor (part winding 1)
K2 Mains contactor (part winding 2)
K1T Delay relay max. 1s
S1 Control voltage switch
E1 Oil sump heater
nderung
0
Datum Name
Datum
Bearb.
Gepr.
Norm
1
20.Feb.2009
Kelich
09.M„r.2010
Urspr.
2
Ers.f.
3
Ers.d.
4
PWMP10
5 6 7
BOCKCOMPRESSORS
8
=
+
9
Bl.
1
Bl.
1
XSS
Q1
L1 L2 L3 NPE
AnschluákastenVerdichter
I=66%
F1.1
K1
1
2
1
3
4
2
5
6
3
1U1
1V1
1W1
PE
M
Y/YY
M1
R1
2U1
2V1
2W1
I=33%
F1.2
K2
1
2
4
3
4
5
5
6
6
X1 L1 L1 N N 43 43 11 12 14
LSM
X2123456
7
F1.1
F1.2
8
R2
4A
F2
S1
910
MP10
11
F5
K1
12
T2
13
N
P™l
14
L
15
M
16
S
P>
F3
17 18 19
K1
P
F4
20
K1
K1T
K2
21 22
K1T
P<
B1
23 24
K1
25
E1
26
L1.1
L2.1
L3.1
L1.2
N
PE

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5|Electrical connection
400 V
Direktstart YY Teilwicklungsstart Y/YY
1V1 1W11U1
2W12V12U1
L3L2L1 L3L2L1
L3L2L1
1V1 1W11U1
2W12V12U1
Direct start YY
Part winding start Y/YY
ATTENTION! Failuretodo this resultsinopposed rotary elds andresultsin
damage to the motor. After the motor starts up via partial winding
1,partialwinding2mustbeswitchedonafteramaximumdelayof
one second . Failure to comply can adversely affect the service life
of the motor.
The motor is wired for direct start (YY) at the factory. For part winding start Y / YY, the bridges must be
removed and the motor feed line connected according to the circuit diagram:

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5|Electrical connection
5.4 Special motor: design for direct or star-delta start
Amechanicalunloadedstartwithbypasssolenoidvalve(accessories)isrequiredforthe
star-delta start.
Designation on the name plate Sticker on the terminal box
∆/ Y
Star-deltastart-upisonlypossiblefor230Vpowersupply.Example:
230V∆
Direct start Star-delta start
400VY
Direct start only
∆
∆
∆
V1 W1
U1
V2
U2
W2
L3L2L1
∆
∆
∆
L3L1
V1 W1
U1
V2
U2
W2
L1 L2 L3
L2
∆
∆
∆
V1 W1U1
V2U2W2
L1 L2 L3

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nderung
0
Datum Name
Datum
Bearb.
Gepr.
Norm
1
20.Feb.2009
Kelich
09.M„r.2010
Urspr.
2
Ers.f.
3
Ers.d.
4
D/S
MP10
5 6 7
BOCKCOMPRESSORS
8
=
+
9
Bl.
1
Bl.
1
XSS
Q1
L1 L2 L3 NPE
F1.1
K1
1
2
F1.2
1
AnschluákastenVerdichter
3
4
2
5
6
3PE
U1
V1
W1
M
3
~
M1
Y
K3
1
2
3
4
R1
5
6
W2
U2
V2
D
K2
1
2
4
3
4
5
5
6
6
X1 L1 L1 N N 43 43 11 12 14
LSM
X2123456
7
F1.1
F1.2
8
R2
4A
F2
S1
910
MP10
11
F5
K1
12
T2
13
N
P™l
14
L
15
M
16
S
K1
K1
K3
P>
F3
K4T
K3
K2
17
K4T
K2
K3
18 19
K4T
P
F4
20
K5T
AL
21 22
K5T
P<
B1
23 24
K1
25
E1
26
L1.1
L2.1
L3.1
L1.2
N
PE
5.5 Basic circuit diagram for star-delta start with special motor
Fig. 20
R1 Cold conductor (PTC sensor) motor winding
R2 Thermal protection thermostat (PTC sensor)
F1.1 /1.2 2 motor protection switches
F2 Control power circuit fuse
F3 High pressure safety monitor
F4 Safety chain (high/low pressure monitoring)
F5 Oil differential pressure monitor
B1 Enabling switch (thermostat)
Q1 Main switch
Compressor terminal box

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© Danfoss | Climate Solutions | 2023.06 AQ452034894212en-000201 | 19
nderung
0
Datum Name
Datum
Bearb.
Gepr.
Norm
1
20.Feb.2009
Kelich
09.M„r.2010
Urspr.
2
Ers.f.
3
Ers.d.
4
D/S
MP10
5 6 7
BOCKCOMPRESSORS
8
=
+
9
Bl.
1
Bl.
1
XSS
Q1
L1 L2 L3 NPE
F1.1
K1
1
2
F1.2
1
AnschluákastenVerdichter
3
4
2
5
6
3PE
U1
V1
W1
M
3
~
M1
Y
K3
1
2
3
4
R1
5
6
W2
U2
V2
D
K2
1
2
4
3
4
5
5
6
6
X1 L1 L1 N N 43 43 11 12 14
LSM
X2123456
7
F1.1
F1.2
8
R2
4A
F2
S1
910
MP10
11
F5
K1
12
T2
13
N
P™l
14
L
15
M
16
S
K1
K1
K3
P>
F3
K4T
K3
K2
17
K4T
K2
K3
18 19
K4T
P
F4
20
K5T
AL
21 22
K5T
P<
B1
23 24
K1
25
E1
26
L1.1
L2.1
L3.1
L1.2
N
PE
M1 Compressor motor
K1 Mains contactor
K2 ∆-contactor
K3 Y-contactor
K4T Delay relay for contactor changeover
K5T Delay relay for start unloader
S1 Control voltage switch
AL Start unloader
E1 Oil sump heater

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5|Electrical connection
ATTENTION!
Terminals 1 - 6 on the trigger
unit MP 10 and terminals PTC
1 and PTC 2 on the compres-
sor terminal board must not
come into contact with mains
voltage. This would destroy the
trigger unit and PTC sensors.
The supply voltage at L1-N
(+/-forDC24Vversion)must
be identical to the voltage at
terminals11,12,14and43.
5.6 Electronic trigger unit MP 10
The compressor motor is tted with cold conductor temperature sensors (PTC) connected to the
electronic trigger unit MP 10 in the terminal box. Readiness to operate is signalled by the H3 LED
(green) after the power supply is applied. In the case of excess temperature in the motor winding, the
unit switches off the compressor and the H1 LED lights red.
The hot gas side of the compressor can also be protected against overtemperature using a thermal
protection thermostat (accessory). The H2 LED (red) is provided for the protection function.
The unit trips when an overload or inadmissible operating conditions occur. Find and remedy
the cause.
5.7 Connection of the trigger unit MP10
INFO! Connect the trigger unit MP10 in accordance with the circuit dia-
gram.Protectthetriggerunitwithadelayed-actionfuse(F)ofmax.
4A.Inordertoguaranteetheprotectionfunction,installthetrigger
unitastherstelementinthecontrolpowercircuit.
Temperature monitoring connections:
Motor winding: Terminals 1 - 2
Thermal protection thermostat: Terminals 3 - 4
Restart prevention: Terminals 5 - 6
INFO! Theunithasarestartpreventiondevice.Afteryouhaverectiedthe
fault,eitherinterruptthemainsvoltage.Thisunlockstherestartpre-
vention device and the LEDs H1 and H2 go out.
Terminal board
Fig. 21