ESB-130-8
34
5.5
Protection devices
5.5.1
SE-B2 and SE-B3
The compressors are equipped with the SE-B2 or SE-
B3 protection device in the standard configuration (with
temperature monitoring). Optionally the SE-E1 or SE-
G1 can also be operated with additional functions.
Additional monitoring functions of the SE-E1 and SE-
G1:
• Rotation direction
• Phase failure
The SE-G1, a version of the SE-E1, is equipped with a
modified phase failure and rotation direction monitoring
function. Thus it is suitable for direct-on-line start and
operation with soft starter.
Connect protection devices according to the schematic
wiring diagram in the terminal box.
!
!
NOTICE
Potential failure of the compressor protection
device and the motor due to improper connec-
tion and/or faulty operation!
The terminals B1-B2 on the protection device
and the corresponding terminals on the com-
pressor as well as the two sensor cables must
not come into contact with the control voltage or
operating voltage!
5.5.2
Discharge gas temperature sensor (option)
In case of operation near application limits, it is abso-
lutely required to use a discharge gas temperature
sensor!
• ORBIT 6: Mount the discharge gas temperature
sensor on the discharge gas line using the clip and
insulation provided for this purpose. Distance from
discharge nozzle: 127 mm (5 inch).
• ORBIT 8: Remove the Schrader valve from the HP
connection and install the sensor element. For OR-
BIT 8 compressors without HP connection, the dis-
charge gas temperature sensor must be mounted on
the discharge nozzle using the clamp-on housing
supplied in the BITZER accessories kit.
5.5.3
Pressure switch (HP + LP)
Pressure switches are required for securing the com-
pressor's application range in order to avoid unaccept-
able operating conditions. Connection positions see
connection diagrams. Cut-in and cut-out pressure val-
ues must be checked prior to commissioning of the sys-
tem.
Settings
ORBIT 6
• Low-pressure switch: min. 2.4 bar
• High-pressure switch: min. 44 bar
ORBIT 8
• Low-pressure switch: min. 2.4 bar
• High-pressure switch: min. 42 bar
For special applications, such as heat pumps, the low
pressure may fall below 2.4 bar for a short time. To
avoid unnecessary cut-out due to low pressure, it is
possible to set a second lower value.
However, this pressure setting may not fall below 1.0
bar. Additionally, operation in this range is limited to 60
seconds maximum when starting the compressor for
the first time.
The given values are excess pressure values.
5.5.4
Oil heater
The oil heater ensures the lubricity of the oil even after
long shut-off periods. It prevents increased refrigerant
concentration in the oil and therefore reduction of vis-
cosity.
The oil heater must be operated while the compressor
is at standstill in case of
• outdoor installation of the compressor
• long shut-off periods
• high refrigerant charge
• possible refrigerant condensation in the compressor
For some low refrigerant charge systems and applica-
tions, oil heaters may not be required. Contact BITZER
for application guidance.
For all ORBIT compressor models the oil heater must
be mounted below the sight glass (see figure 9, page
35 und see figure 10, page 35). Make sure that the
heater firmly rests on the housing on both sides of the
vertical weld seam. Carefully tighten the screw and
make sure that the heater is evenly clamped over its
entire length around the housing and firm contact of the
contact points is ensured.
