MOGlabs MOA, Manual, Page: 15 / 66

2. Safety features
WARNING
Do not operate the amplifier above the
Maximum current, unseeded
without an appropriately coupled input seed. Operation exceeding that
condition can cause fatal structural degradation of the
TA
diode. Refer to
the
Maximum current, unseeded
specified in the amplifier test report.
MOGLabs amplifiers have interlocks for customer protection and internal
power monitoring with a safety shutoff feature to protect the
TA
diode.
The shutoff feature shuts off the
TA
diode current if simultaneously the
amplifier operates above the
Photodiode safety cutout
current specified
in the system test report, and the internal power is less than a factory
determined threshold.
2.1 Interlock
An interlock switch located along the top edge of the chassis is activated if
the cover is removed while the
TA
injection current is above the
Maximum
current, unseeded
current (see fig. 1.1). The interlock can be defeated
for alignment and test purposes by holding the switch actuator down, for
example with adhesive tape, or by changing the interlock mode under the
headboard settings in the
LDD
menu.
2.2 Photodiode safety cutout
A photodiode monitors the output power of the
TA
diode. Once the
TA
injection current is above the photodiode
safety cutout current
, if the out-
put power is measured low for a requested
TA
diode current, for example
because the seed input has been blocked, the diode current supply will be
switched off to prevent damage to the
TA
diode.
Two locations for the photodiode are possible. The first location is inside
the exit cover plate of the amplifier U-chassis, which detects light reflected
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