Stanford Research Systems LDC500, Руководство по эксплуатации и обслуживанию

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2 – 8 Getting Started
2.2.3 Verify TEC wiring polarity
If you are setting up a new TEC load, it is important to verify the
TEC polarity. This can be done either manually or by performing
an autotune (see section 2.2.4, below). The following procedure is a
simple method to manually verify the TEC wiring polarity.
•
Verify the temperature sensor is correctly configured. See sec-
tion 2.2.1 for details.
•
If on, turn o
ff
the TEC by pressing the [TEC On
/
O
ff
] button.
•
Place the instrument in constant current mode by pressing the
[Temp
/
Current] button until the CC indicator is illuminated in
the Control Mode section.
•
Press the TEC [Monitor] button, and then press [ ] or [ ] until
the “TEC Monitor: T” display appears.
•
If necessary, wait until the temperature stabilized near room
temperature.
•
Press the TEC [Set] button, and then press [ ] or [ ] until the
“TEC Settings: TE I:” display appears. Using the keypad, enter
the value around 10 % of the maximum current. Be sure to
press [Enter] to complete the entry.
•
Press the TEC [Monitor] button. The temperature display
should reappear on the alphanumeric display.
•
Press the [TEC On
/
O
ff
] button to turn on the TEC output.
•
Watch the temperature monitor display: the temperature
should begin
decreasing after a moment. Press the [TEC On
/
O
ff
]
button again to turn o
ff
the TEC current. In this case, the TEC
wiring polarity is correct.
•
If the temperature
increases
, turn o
ff
the TEC output by pressing
[TEC On
/
O
ff
]. In this case, the TEC wiring polarity is reversed.
2.2.3.1 Correcting the TEC polarity
If you discover the TEC wiring polarity is reversed, there are two
approaches to fix the problem.
1. The preferred solution is to physically correct the wiring, re-
versing the current leads to the TEC element. This approach
leaves the setup correctly configured for future use.
2. If it is inconvenient to physically rewire the TEC, the polarity
assignment of the DB–15 TEC connector for TEC
+
current
and TEC
−
current can be reversed with the
TPOL
command
LDC500 Series Laser Diode Controllers