5
FRCC.EI.003.A6.02 © Danfoss Commercial Compressors 01/14
sh 240 - 295 - 300 - 380 - 485
sy 240 - 300 - 380
sz 240 - 300 - 380
These Danfoss compressors
motors are protected by an external module
protecting against phase loss/reversal, over heating and high current
draw.
A1
A3
A2
MPM
S
KS
LPS
CC
Legend:
Fuses ..........................................................................................F1
Compressor contactor .........................................................KM
Control relay ...........................................................................KA
Safety lock out relay .............................................................. KS
Optional short cycle timer (3 min) ............................... 180 s
External overload protection ...............................................F2
Pump-down pressure switch ...............................................LP
High pressure safety switch.................................................HP
Control device .........................................................................TH
Liquid Line Solenoid valve ............................................... LLSV
Discharge gas thermostat ................................................DGT
Fused disconnect ...................................................................Q1
Motor safety thermostat ................................................... thM
Compressor motor ................................................................. M
Motor Protection Module ............................................... MPM
Thermistor chain.......................................................................S
Safety pressure switch ........................................................ LPS
Control circuit ........................................................................CC
All Wiring diagrams are with pump-down cycle
Instructions
1 – Introduction
These instructions pertain to the Danfoss SM,
SY, SZ, SH & WSH scroll compressors used for air-
conditioning systems. They provide necessary
information regarding safety and proper usage
of this product.
2 – Handling and storage
• Handle the compressor with care. Use the
dedicated handles in the packaging. Use the
compressor lifting lug and use appropriate
and safe lifting equipment.
• Store and transport the compressor in an
upright position.
• Store the compressor between -35°C and 50°C.
• Don’t expose the compressor and the packa-
ging to rain or corrosive atmosphere.
3 – Safety measures before assembly
Never use the compressor in a flammable
atmosphere.
• The compressor ambient temperature may
not exceed 50°C during off-cycle.
• Mount the compressor on a horizontal flat
surface with less than 3° slope.
• Verify that the power supply corresponds to
the compressor motor characteristics (see
nameplate).
• When installing SZ or SH or WSH, use equip-
ment specifically reserved for HFC refrige-
rants which was never used for CFC or HCFC
refrigerants.
• Use clean and dehydrated refrigeration-grade
copper tubes and silver alloy brazing material.
• Use clean and dehydrated system components.
• The piping connected to the compressor must
be flexible in 3 dimensions to dampen vibrations.
4 – Assembly
• In parallel assemblies of SH, WSH, SM112 - 124
- SM/SZ147 the compressor requires a rigid
mounting on the rails. Use the rigid spacers
from the tandem mounting kit or the rigid spa-
cers delivered with dedicated tandem com-
pressors.
• Slowly release the nitrogen holding charge
through the schrader port.
• Remove the gaskets when brazing rotolock
connectors.
• Always use new gaskets for assembly.
• Connect the compressor to the system as
soon as possible to avoid oil contamination
from ambient moisture.
• Avoid material entering into the system while
cutting tubes. Never drill holes where burrs
cannot be removed.
• Braze with great care using state-of-the-art tech-
nique and vent piping with nitrogen gas flow.
• Connect the required safety and control de-
vices. When the schrader port is used for this,
remove the internal valve.
•
Do not exceed the maximum tightening
torque for rotolock connections:
Rotolock connections Tightening torque
1” rotolock
80 Nm
1 1/4 “ rotolock
90 Nm
1 3/4” rotolock
110 Nm
2 1/4” rotolock
130 Nm.
5 – Leak detection
Never pressurize the circuit with oxygen or
dry air. This could cause fire or explosion.
• SM 084 to 185, SY 380, SZ 084 to 185, SZ 380, SH
090 to 184, WSH 090 to 184: Pressurize the system
on HP side first and then on LP side. Never let the
pressure on LP side exceed the pressure on HP
side with more than 5 bar. Such pressure diffe-
rence could cause internal compressor damage.
• Do not use dye for leak detection.
• Perform a leak detection test on the complete
system.
• The test pressure must not exceed :
Models
LP side
HP side
SY / SZ 240 - 380
20 bar
32 bar
SM / SZ 84 - 185
25 bar
32 bar
SH 180 - 485
30 bar
45 bar
SH / WSH 090 - 184 33 bar
45 bar
• When a leak is discovered, repair the leak and
repeat the leak detection.
6 – Vacuum dehydration
• Never use the compressor to evacuate the
system.
• Connect a vacuum pump to both the LP & HP
sides.
• Pull down the system under a vacuum of 500
µm Hg (0.67 mbar) absolute.
• Do not use a megohmmeter nor apply power
to the compressor while it is under vacuum as
this may cause internal damage.
7 – Electrical connections
• Switch off and isolate the main power supply.
See overleaf for wiring details.
• All electrical components must be selected as per
local standards and compressor requirements.
• Refer to page 2 for electrical connections details.
• The Danfoss scroll compressor only works
correctly in one rotation direction. Line
phases L1, L2, L3 must absolutely be connec-
ted to compressor terminals T1, T2, T3 to
avoid reverse rotation.
• Use ø 4.8 mm (3/16”) screws and ¼” ring ter-
