28
AGL_Stream_ST_A2L_A1_4M_6M_EN_Rev00
Legend
A1 ....... CoreSense Protection module
K1 .......... Contactor M1
A2 ....... OPS2 Oil pressure switch
K2 .......... Contactor M1 Y-connection
A5 ....... Compressor terminal box
K3 .......... Contactor M1
Δ-connection
F6 ....... Fuse for control circuit
M21 ........ Fan motor / condenser
F7 ....... Fuse for control circuit
R2 .......... Crankcase heater
F8 ....... Fuse for control circuit
Y21/22 ... Solenoid valve capacity controls
F10 ..... Thermal protection switch M21
Y3 .......... Solenoid valve unloaded start
Figure 33: Wiring diagram
– Star/Delta motors (EW…)
4.5.3.3
Oil differential pressure control
The oil pressure switch breaks the control circuit when the pressure difference between the oil pump
outlet and the crankcase is too low. The switch must be properly adjusted and tamper-proof. If the
oil differential pressure drops below the minimum acceptable value the compressor will be stopped
after a 120-second delay. After having solved the problem the control has to be reset manually.
NOTE: Proper oil pressure safety control with an approved switch is a condition of warranty!
The following oil pressure switches can be delivered as accessories:
▪
Electronic oil pressure switch OPS2
▪
Mechanical oil pressure switch ALCO FD-113ZU, applicable only for A1 refrigerants
Electronic oil pressure switch
– Alco Controls OPS2
WARNING
Ignition source in a potentially flammable atmosphere! Fire hazard!
The
electronic oil pressure switch is not an ignition source during normal operation
in an A2L-refrigerant system but could become one if not installed and
connected properly.
