Since replacing the crystal chiller flow sensor did not fix the problem with the laser tripping out,
we replaced the water manifold located under the PSL table.  Attached are two traces from when the
chiller tripped out.  Since the power meter circuit tripped before the front end circuit, this suggested
that the problem really was with the power meter flow sensor rather than the chiller (see attached
plots).

    The pressure regulators on the manifold were adjusted to give a front end flow rate of 1.7 lpm,
the power meter circuit 1.5 lpm and the laser heads 0.6 lpm as indicated by the Beckhoff PC.  Note
that the flow for head 4 is different at 0.5 lpm, although head 4 has always been a bit odd of late.
 - 4 bar for the MOPA circuit
 - 4.46 bar for the power meter circuit
 - 4.35 bar foe the laser heads circuit

    It is possible that there is a slow leak at the bottom of the power meter flow sensor.  We will be
monitoring the crystal chiller water level over the next few days to see if indeed there is a leak.

    Laser restarted.  Things seem to be okay for now, at least.


JeffB/Jason/Peter