Sumitomo SRDK Series - 4 FUNCTIONAL CHECK; 4-1 SIMPLE PROBLEM; 4-1-1 PRESSURE

OPERATION MANUAL Sumitomo Heavy Industries, Ltd.
SRDK Series CRYOCOOLER 41
4-1 SIMPLE PROBLEM
4 FUNCTIONAL CHECK
4-1 SIMPLE PROBLEM
This section describes several simple problems that usually occurred. If you have trouble that you cannot
fix according to the following procedure, proceed to “TROUBLE SHOOTING FLOW CHART” described in
Section 6.
4-1-1 PRESSURE
Cryocooler is designed and manufactured to get cooling capacity with specified Helium Gas Pressure. It is
highly recommended to check the pressure. If the indicated pressure is higher than specified value,
reduce the pressure. If it is lower, charge the helium gas. See “TECHNICAL INSTRUCTION” of Cold
Head used, to see the specified pressure of your system.
COLD HEAD MODEL STATIC PRESSURE
RDK-408D2 4K Cold Head
RDK-408D 4K Cold Head
RDK-415D 4K Cold Head
1.60 - 1.70 MPa at 20 deg.C (68 deg.F)
(16.3 - 17.3 kgf/cm
2
G, 232 - 246 psig)
RDK-408S2 10K Cold Head
RDK-408S 10K Cold Head
RDK-400B Single Stage Cold Head
1.45 - 1.55 MPa at 20 deg.C (68 deg.F)
(14.8 - 15.8 kgf/cm
2
G, 210 - 225 psig)
After replacing Cold Head, it will be necessary to charge the Helium Gas because the temperature of the
Cold Head is usually lower than room temperature, therefore the system always lose helium gas.
4-1-2 ROOM TEMPERATURE
Room temperature affects the Cryocooler performance. It is highly recommended to keep the room
temperature in the specified range. See “TECHNICAL INSTRUCTION” of Compressor Unit used, for
details.
COMPRESSOR UNIT MODEL ROOM TEMPERATURE RANGE
CSA-71A, CSW-71C, CSW-71D
5 to 28 deg.C (41 to 82.4 deg.F)
28 to 35 deg.C (82.4 to 95 deg.F) with 5% Capacity Loss
4-1-3 MAIN POWER PHASE
The Cryocooler operates with 3 phase mains frequency. The Compressor Units are equipped with phase
reverse protection circuit to protect the Compressor Unit from reverse revolution. The Compressor Unit
will not start, in case the main power is reverse phase. A procedure for the diagnosis of phase failure for
input power caused by miss-wiring will be performed, if the Compressor Unit cannot be operated as normal
in a condition of the “Drive Switch - ON” under the “Main Power Switch - ON”.