TK 56612-18-IM-EN
37
SPR and CPR Adjustment Procedures
MODEL
SPR
CPR
V-520 RT 10 / 10 MAX
V-520 RT 20 / 20 MAX
X
V-520 RT 30 / 30 MAX
X
V-520 RT 50 / 50 MAX
X
X
V-520 RT SPECTRUM
X
X
SPR Valve Settings
The SPR valve located in the Refrigeration Module is used to limit the load on the standby compressor. This also affects
the current draw on the electric motor. Monitor the current draw of the electric motor when making this adjustment and
keep it at least 1.5 amps below the overload relay setting. Refer to the unit Maintenance Manual for overload settings.
N
No
otte
e:: The following procedures are for initial settings. Sometimes conditions such as high or low ambient
temperatures may require that the settings be fine-tuned for optimum performance.
1. Install a gauge manifold set on the electric standby compressor. Attach an additional compound gauge to the
suction service port on the copper tube directly before the SPR valve to monitor suction pressure at the inlet to the
suction pressure regulator.
2. Connect the unit’s power receptacle to an appropriate electric power source.
3. Place a jumper wire between the 1
12
2 and C
CH
HB
B wires at the defrost termination switch to ensure the unit will run in
Defrost.
4. Start the unit and run it in Defrost on the electric standby compressor until the pressure on the additional compound
gauge attached to the service port stabilizes at a pressure above 45 psig (310 kPa).
5. Check the suction pressure on the gauge attached to the suction service port at the standby compressor. It should
be 39.0 ± 4 psig (269 ± 28 kPa) for 230V 3 phase electric motor, and 24.0 ± 4 psig (165.5 ± 28 kPa) for 230V 1 phase
electric motor. If the setting is incorrect, remove the protective cap and adjust the suction pressure regulator valve
to the correct setting.
6. Remove the gauge manifold set, the additional compound gauge, and the jumper wire when finished with the
procedure.
Summary of Contents for V-520 RT Series
Page 32: ...32 TK 56612 18 IM EN E El le ec ct tr ri ic ca al l C Co on nn ne ec ct ti io on ns s ...
Page 42: ...42 TK 56612 18 IM EN Component Dimensions and Weights Figure 1 ES500 EVAPORATORS ...
Page 54: ...54 TK 56612 18 IM EN N No ot te es s ...