Monitoring And Protective Functions - Bitzer CM-SW-01 Original-Gebrauchsanweisung

Oil injection and oil return from the secondary oil
separator
During compressor operation, the module opens the
solenoid valve in the oil injection line (Y1, HS.95/
OS.95) or the solenoid valve in the oil return line from
the secondary oil separator (Y9, OS.85). This function
can be used as an option.
Oil heater in CS. compressors
The module maintains the oil temperature 20 K above
the refrigerant's saturation temperature. For this pur-
pose, it switches the oil heater on and off even when
the compressor is at standstill, thus increasing the sys-
tem's overall efficiency.
Control of the motor contactors at compressor start
The compressor module controls the activation and de-
activation times of the motor contactors.
Star-delta motor: The contact at terminal CN2:2 (K1
Control) closes 1 s after the start signal and reopens
after further 2 s. The contact at terminal CN2:1 (K2
Control) closes 1.5 s after the start signal and remains
closed until the compressor is shut off.
Part winding motor: The contact at CN2:2 (K1 Control)
closes 1 s after the start signal. The contact at CN2:1
(K2 Control) closes 0.5 s afterwards. Both contacts re-
main closed until the compressor is shut off.
Motor for direct on-line start: The contact at terminal
CN2:2 (K1 Control) closes 1 s after the start signal and
reopens when the compressor is shut off. The contact
at terminal CN2:1 (K2 Control) is not used.
The terminal assignment chosen for the module pre-
vents a short-circuit from occurring if the time relay con-
trol set in the module does not correspond to the motor
used. For setting the time relay control to match the
motor, refer to see chapter Selecting the motor start
function, page 22.

4.2 Monitoring and protective functions

The compressor module monitors the signals from sev-
eral sensors located on the compressor:
Monitored Com-
function pressor
Application lim- All
its:
Condensing
and evapora-
tion temperat-
ure
ST-150-3
Measuring sensor
Low pressure and high
pressure transmitters
(B7 and B6)
Monitored Com-
function pressor
Low pressure All
High pressure All
Discharge gas HS./OS.
temperature
Oil temperature CS.105
Oil supply HS.95/
OS.95
OS.85
Minimum oil CS.105
level
Oil stop valve OS.85
Motor temper- HS./
ature CS.105
Rotation direc- HS./
tion CS.105
The compressor module compares the measured val-
ues with programmed data, sending signals via Mod-
bus and indicating the operating condition by means of
differently coloured LEDs. The compressor will be cut
out in case of operation beyond the application limits,
lack of oil, excessive motor temperature, wrong rotation
direction or critical motor start, see chapter Protective
functions, page 17. The module issues warnings when
the compressor starts too frequently or insufficiently un-
loaded, or when the minimum running time or minimum
shut-off period is not met.
Oil pressure transmitter (B9)
For HS.95 compressors, this component is part of the
standard scope of delivery.
For OS.95, the oil pressure transmitter can be supplied
as an option. Compressors from serial number
1092401124 can be retrofitted with the oil pressure
transmitter, which requires a firmware update. The
state of delivery of the respective OS.95 compressor is
indicated on the label attached inside the module hous-
ing.
Measuring sensor
Low pressure transmit-
ter (B7)
High pressure transmit-
ter (B6)
Discharge gas temper-
ature sensor (R2)
Oil temperature sensor
(R2)
Opto-electronic oil mon-
itoring (F25)
Oil pressure transmitter
(B9, see below for de-
tails)
Oil supply monitoring
(F7)
Opto-electronic oil mon-
itoring (F8)
Valve monitoring in the
oil filter chamber (F9)
PTC sensors in motor
windings (R3..8)
Instrument leads on the
bolts of the motor
power supply
7