Bruker AXS Typ BR 058-31, Инструкция по монтажу и эксплуатации

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02-2010 13
In the case of pure water outlets without heat exchanger, for each cooling circuit a
dedicated consumer pump is required in addition to the main water pump. In this case the
secondary consumer pumps must be protected against dry-run. This protection is ensured
through complete opening of the mixer valves for 2 minutes and operating the main water
pump after starting-up the chiller. After 2 minutes the secondary consumer pumps are
switched on. This ensures sufficient water supply for the secondary consumper pump after
chiller start-up.
Option: Heating
The heating has the function of heating-up the medium to a certain temperature. Switching
over from cooling to heating and reverse takes place manually or automatically at the
regulator. The temperature is controlled by the regulator. For further details see Operating
Instructions- “Regulator”.
Option: User height
A solenoid valve in the return flow to the refrigeration unit and a non-return valve in the
refrigeration unit prevent discharges, that cooling medium runs back into the tank, when a
user stands higher than the refrigeration unit and when the pump does not run, i.e. when
the refrigeration unit is switched off.
Option: Winter pressure regulation
A pressure switch in the cooling agent circuit compulsively switches the ventilator off in
case of low surrounding temperatures under 8°C, until the system has enough higher
pressure, so that a circulation of cooling agent in the system is safeguarded.
Any other or excessive/outside the intended limits use thereof is regarded as non-designed
usage.
Option: Excessive flow valve
Instead of the constant bypass, which protects the pump from a customer-sided closed
slide valve and the cooling medium runs constantly between forward and reverse flow via
the bypass, there is a pressure-controlled bypass installed in some of the units, according
to the customer requirements. This only opens above a preset pressure and ensures that
the system is never exposed to a pressure higher than that preset.
Option: Level early-warning
The use of a second level indicator enables the issuance of an early-warning when the
level in the reservoir sinks and there is a danger of a shut-off via the normal level indicator.
This allows sufficient time to refill the vessels, without the low cooler level causing a switch-
off.
Option: Reference-driven regulation
In this case no fixed values are set at the regulator. The refrigeration unit orientates itself
around a reference value via a second sensor, for example at the surrounding temperature
or at the machine bed. The temperature of the refrigeration unit is then carried through
according to the change in the refence value. What is carried through can be limited to a
certain temperature range e.g. under 15 °C or on the other hand above 35°; here the
refrigeration unit can be set automatically to a fixed value which has to be entered.
Option: Dirt trap / Filter