Lake Shore 625, Руководство пользователя

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Lake Shore Model 625 Superconducting MPS User’s Manual
3-4 Installation
3.3.4 Power Switch
The power switch is on the front panel of the Model 625 and turns line power to the instrument On and Off. When the
circle is depressed, power is Off. When the line is depressed, power is On.
3.4 MAGNET CABLE CONNECTIONS
Magnet cable connections are made at the +OUTPUT and –OUTPUT terminals on the rear panel. These plated copper
bus bars accommodate ¼ inch (M6) mounting hardware. Use load wires heavy enough to limit the voltage drop to less
than 0.5 volts per lead. This ensures proper regulation and prevents overheating while carrying the output current. The
remote voltage sense leads can be used to measure the actual magnet voltage. Keep conductor temperature under 85 °C
(185 °F) for a 35 °C (95 °F) ambient. Table 3-1 lists the current capacity and total lead lengths for load connections.
Lake Shore sells magnet cables in 10 and 20 foot lengths. Refer to Paragraph 6.2 for ordering accessories.
Table 3-1. Current Capacity and Total Lead Lengths
AWG
Area
(mm
2
)
Capacity
(A)
Resistivity

/1000 feet
Total Lead Length (feet)
60 A 120 A
0 53.5 245 0.09827 170 85
2 33.6 180 0.1563 107 53
4 21.2 135 0.2485 67 34
6 13.3 100 0.3951 42
—
8 8.4 75 0.6282 27
—
3.5 ANALOG INPUT/OUTPUT CONNECTIONS
The Analog I/O connector provides connections to analog signals used to monitor or control the power supply. Two
inputs are provided, one to program the current output and one used to monitor the remote voltage sense leads. Two
outputs are also provided to monitor the output current and the output voltage. Refer to the instrument specifications in
Paragraph 1.2 for input and source impedances.
Analog_Output.bmp
Pin Name Pin Name
1
2
3
4
5
6
7
8 Voltage Sense –
NC
Current Program –
NC
Voltage Monitor –
NC
Current Monitor –
NC
9
10
11
12
13
14
15
Voltage Sense +
NC
Current P
NC
Voltage M
NC
Current M
Figure 3-3. Model 625 Analog Input/Output Connector
3.5.1 External Current Programming
The output current can be programmed externally using an analog voltage. This programming voltage can also be
summed with the internal current setting. Refer to Paragraph 4.18 to change the external program mode. The external
current programming input is a differential input with a sensitivity of 1 V = 10 A and an input impedance of > 50 k

.
The programming voltage is limited internally to approximately ±6.1 V but care must be taken to insure that maximum
current capability of the magnet is never exceeded.