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WATER-COOLED CONNECTIONS PAGE | 29
• Because cooling tubing is specified in inch sizes, the use of metric tubing fittings is discouraged
unless you have installed the appropriate inch-to-metric tubing adaptors. The use of metric fit-
tings on inch size tubing will lead to coolant leaks or may allow the pressurized tubing to blow off
the fitting.
Coolants
NOVANTA recommends that the laser’s cooling fluid contain at least 90% water (distilled or tap) by vol-
ume. In closed-loop systems, use a corrosion inhibitor/algaecide such as Opti shield Plus or equivalent.
Avoid glycol-based additives because they reduce the coolant’s heat capacity and high concentrations
may affect power stability. For NOVANTA lasers, the minimum coolant setpoint is 18 °C (64 °F) so glycol
is not necessary unless the chiller is subjected to freezing temperatures. In applications where biocides
containing chlorides are used, concentrations should not exceed 25 parts per million (PPM). Maintain a
coolant pH level above 7.0. We recommend the installation of a filter on the chiller’s return line,
especially in areas where water hardness is a problem. V30 lasers incorporate the following wetted
materials in the coolant path—aluminum, brass, copper, Delrin®, PBT, polyethylene, stainless steel, and
Viton®.
Important Note: DO NOT use de-ionized (DI) water as a coolant. DI water is unusually corrosive
and is not recommended for mixed material cooling systems.
Setting coolant temperature
Choosing the correct coolant temperature is important to the proper operation and longevity of your
laser. When coolant temperature is lower than the dew point (the temperature at which moisture
condenses out of the surrounding air), condensation forms inside the laser housing leading to failure of
laser electronics as well as damage to optical surfaces.
The greatest risk of condensation damage occurs when the laser is in a high heat/high humidity environ-
ment and the chiller’s coolant temperature is colder than the dew point of the surrounding air or when
the system is shut down, but coolant continues to flow through the laser for extended periods of time.
The chiller’s temperature setpoint must always be set above the dew point temperature. In cases where
this is not possible within the specified coolant temperature range of 18 °C–22 °C (64 °F–72 °F), then the
following steps MUST be taken to reduce the risk of condensation damage.
•
Air-condition the room or the enclosure containing the laser.
• Install a dehumidifier to reduce the humidity of the enclosure containing the laser.
• Stop coolant flow when the laser is shut down.
• Increase coolant flow by an additional 3.8 lpm (1.0 GPM). Do not exceed a coolant pressure of 414
kPa (60 PSI).
Table on the following page provides dew point temperatures for a range of air temperature and relative
humidity values. Remember that the laser’s coolant temperature must be set above the dew point