ILX Lightwave LDC-3700C Series, Руководство пользователя, Страница: 58 / 176

O P E R A T I O N S
Functions and Features
42
LDC-3700C Series
C H A P T E R
2

All functions of the temperature controller can be utilized as in normal TEC
operation with the exception of the TE Current Limit. When the controller is
configured in BOOSTER MODE, the LIM I value may be increased above the
normal operating maximum of 4.0 Amps, to a maximum of 10.0 Amps. The
control signal voltage, ±10 V is linearly proportional to the control current, which is
limited by the
LIM I parameter.
Pins 11 and 12 are outputs from the TEC controller hardware. These lines are
TTL-level indicators of the TEC voltage and limit conditions, respectively. They are
useful for external sensing of these conditions in addition to the normal status
reporting of the LDC-3700C Series instrument.
Pin 13 is used as an external shutoff switch. Although it is labeled as "Temp.
Limit", its function is to shut off the TEC controller. This function is controlled by
applying a TTL-level signal to pin 13. When this input is high, the LDC-3700
Series instrument will shut the TEC controller off.
The feedback loop GAIN will require adjustment when a booster current source is
used. The higher thermal loads will require larger or smaller GAIN values in order
to settle to the set temperatures in a desirable fashion. See "Setting TE Control
Loop Gain" in Chapter 2.
For remote operation using the GPIB interface, during controller operation, the
Booster Enabled condition is reported in the TEC Condition Status register. If the
status of the connection between the
BOOSTER PRESENT and DIGITAL
GROUND changes, this event will also be reported in the TEC Event Status
Register. These events may be used to trigger a service request.