Operator`s manual

maintenance/
troubleshooting
415
Synrad Firestar t-Series operator’s manual
Troubleshooting
On systems using remote interlocks, check to see that a positive or negative voltage (±5–24 VDC) is applied
to Pin 3, Remote Interlock, with respect to Pin 11, Input Common, on the User I/O connector (refer to
User I/O connections in the Technical Reference chapter for details). For systems not using interlocks, con-
nect the factory-supplied Quick Start Plug to the User I/O connector on the RF supply’s rear panel or wire
your male DB-15 connector so that Pin 11 (Input Common) is jumpered to Pin 12 (Auxiliary DC Power
Ground) and Pin 3 (Remote Interlock) is jumpered to Pin 4 (+5 VDC Auxiliary Power).
Symptom:
■ An over temperature fault is indicated:
INT LED – Green Interlock Open – Open
TMP LED – Red Over Temperature – Closed
RDY LED – Off Laser Ready – Open
SHT LED – Blue Shutter Open – Closed
LASE LED – Off Laser Active – Open
Possible Causes:
■ Water-cooled lasers – Cooling water temperature is above 22 °C (72 °F) or there is inadequate water
flow through the laser.
Check that your chiller is maintaining a water temperature between 18–22 °C (64 °F–72 °F) at a flow rate
of 2.0 gallons per minute (GPM). If water temperature is OK, check the flow rate. The simplest way to do
this, if a flow meter is not available, is to disconnect the cooling tubing from the chiller inlet (or the drain)
and run the cooling water for one minute into a five-gallon bucket; you should have close to two gallons. If
there is much less than two gallons, check the cooling path for kinked or pinched cooling tubes and check
the chiller for a clogged or dirty filter.
■ Fan-cooled lasers – Cooling fans are not providing adequate airflow to either the laser or the RF
power supply.
Check that all cooling fans are clear of debris and are providing an airflow rate of at least 130 cubic feet
per minute per fan (t60) or 195 CFM per fan (t80/t100). To allow for proper airflow, cooling fans must
have at least 2.25" (57.2 mm) of unobstructed clearance between the outside edge of the cooling fan hous-
ing and any mounting surface or enclosure.
■ The Interconnect cable between the Laser Head and the RF power supply is damaged or disconnected,
causing the temperature circuit to open. Note that an open or disconnected Interconnect cable causes
RDY, SHT, and LASE indicators on the Laser Head to turn off.
Verify that the Interconnect cable is undamaged and that DB-9 connections on both the Laser Head and
RF power supply are tight. Because over temperature faults are latched, you must cycle DC power to reset
the laser.