CONNECTING
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Chiller preparation guidelines
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You must provide fittings to adapt the laser’s 12 mm O.D. polyethylene cooling tubing to the
chiller’s Inlet and Outlet ports. These fittings can be either “quick disconnect” or compression
type fittings.
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Because the i401’s factory-installed fittings and tubing are metric (12 mm), do not use 1/2inch size
tubing or fittings unless you have installed the appropriate adaptors. Mixing inch and metric
tubing/ fittings will lead to coolant leaks or may allow the pressurized tubing to blow off the
fitting.
Coolants
Novanta recommends the laser’s cooling fluid contain at least 90% distilled water by volume. In closed-
loop systems, use a corrosion inhibitor/algaecide such as Opti shield® Plus or equivalent as required.
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. If tap water is used, chloride levels
should not exceed a concentration of 25 parts per million (PPM) and total hardness should be below 100
PPM. Install a filter on the chiller’s return line and inspect frequently. i401 lasers incorporate the following
wetted materials in the coolant path—brass, copper, Delrin®, PBT, polyethylene, stainless steel, and
Viton®.
Note: DO NOT use deionized (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 to 22 °C (64 °F to 72 °F), then
the following steps MUST be taken to reduce the risk of condensation damage.
Caution: Possible Equipment Damage
DO NOT over-tighten Tri Thread fittings as this may deform or damage the O-ring seal and
cause coolant leakage.DO NOT install any other type of fitting into the i401 cooling manifold as
this may damage the manifold threads and/or cause coolant leakage.
