2021/04/17 23:32
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Reconfigurable Laser Servo
Product Manuals - https://www.vescent.com/manuals/
has passed since the previous relock attempt.
Mode A,B,C
These three 2-position slider switches are only accessible by removing the right side panel (see
above) and sets the Hold Time and N+1 Relock Time described above. The 3 positions, A,B,C form a
binary scale factor given by the table below:
C
B
A
Hold Time
N+1 Relock Time
Off
Off
Off
60 µs
150 µs
Off
Off
On
125µs
300 µs
Off
On
Off
250 µs
600 µs
Off
On
On
500 µs
1.25 ms
On
Off
Off
1 ms
2.5 ms
On
Off
On
2 ms
5 ms
On
On
Off
4 ms
10 ms
On
On
On
8 ms
20 ms
The ideal delay used will depend on your system and loop bandwidth. Generally, a faster response
and slower delay is ideal, however, sometimes the system needs time to stabilize after a large
correction and these settings enable the user to adjust how long to wait to let the system stabilize
before engaging the lock.
R202 (Trimpot)
The R202 trimpot sets the size of the window comparator described above. The size of the window
can be measured by the voltage on T3. A smaller window means that the servo is more sensitive to
unlock events and detects them quicker, however, if the window is too small the servo may detect
false positives when the system remains locked but the SERVO OUTPUT is moving quickly to respond
to a challenge.
Back-panel Section
Power I/O (9-pin D-sub)
Never connect this device to a power supply that is switched
on and supplying power. Always turn off the power supply,
make connections to this device, and then re-energize the
power supply.
The power to each electronics module is through a 9-pin D-sub connector through either a power
bridge unit or a serial cable with 9-pin D-sub connectors, which is convenient when the unit must be
taken out of line for access to the side panels. The pin outs are shown in the following figure:
