Synrad p250, User Manual, Page: 95 / 106

TROUBLESHOOTING STATUS LED’S PAGE | 95
Troubleshooting Status LED’s
p250 LED indicators, also mirrored as output signals on the User I/O connector, provide status
information to the user. The prior table shows p250 input/output signal and LED indicator states during
normal and fault conditions. User I/O outputs are Closed when the state indicated by the signal name is
logically True.
On DC power-up, the RDY lamp illuminates yellow when INT and TMP indicators illuminate green. After
the RDY indicator illuminates an internal tickle is enabled. There is a five-second delay before lasing is
permitted. When a Shutter Open Request signal is applied; the internal shutter opens, the SHT LED
illuminates blue, and application of a PWM Command signal causes the LASE indicator to illuminate red
as lasing begins.
For safety reasons, the shutter function on p250 lasers is dependent on the state of the Remote Interlock
input. The Remote Interlock Input status is reflected by the state of INT and RDY indicators. Although a
Shutter Open Request signal may be applied, the SHT LED will not illuminate while the INT LED is red
(RDY LED Off). Therefore, no power is applied to the RF boards until the INT indicator is green (and the
RDY LED is yellow).
The following section illustrates the dependencies of various operating parameters based on the state of
the Remote Interlock input. The conditions shown in bold are those required for lasing to be enabled.
Possible Causes:
•
No voltage is applied to Pin 3 (Remote Interlock) of the User I/O connector.
On systems using remote interlocks, check to see that a positive or negative voltage in the range of 24
±5 VDC is applied to Pin 15. For remote Interlocks, with respect to Pin 11 and Input Common on the User
I/O Connector please refer to User I/O connections in the Technical Reference chapter for details. For
systems not using interlocks, wire a male DB-15 connector to the User I/O connector so that Pin 11 (Input
Common) is jumpered to Pin 12 (Auxiliary DC Power Ground) and Pin 15 (Remote Interlock) is jumpered
to Pin 4 (+5 VDC Auxiliary Power).
On DC power-up of a p250 laser, the RDY lamp illuminates yellow provided INT and TMP indicators
illuminate green. Once the RDY indicator illuminates yellow, an internal tickle is enabled and after a five-
second period lasing is then permitted. When the Shutter Open Request signal is applied, the internal
(EM) shutter opens, the SHT LED illuminates blue, and an application of a PWM Command signal causes
the LASE indicator to illuminate red as lasing begins.
Remote interlock condition
A remote interlock condition occurs when the Remote Interlock input opens. The INT LED is red, and the
Interlock is closed. The (EM) internal shutter mechanism closes, and lasing is halted immediately. On
OEM p250 lasers, a remote interlock condition is not latched. Re-apply the Remote Interlock signal by
reapplying input voltage to that pin and enabling the INT LED to change from red to green. The interlock
(shutter) opens to enable the RDY indicator. Lasing can begin after the five-second delay provided the
SHT indicator is illuminated blue and a PWM Command signal is applied.
Possible Causes:
• No voltage is applied to Pin 14 (Shutter open) of the User I/O connector.
Verify 24 ±5 VDC is applied to Pin 14 (Shutter Open Request). For Pin 15 Input Common on the User, I/O
Connector please refer to the User I/O connections section in the Technical Reference chapter for