Caloritech CX Series, Инструкция по установке, эксплуатации и обслуживанию

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D. OPERATION
RISK OF EXPLOSION Do not operate heater at
voltages higher than the rating specified on the
nameplate. Failure to do this will cause elevated
temperatures.
CAUTION
WARNING
WARNING
Prior to operation an insulation
resistance check must be performed. Heater
with values less than 500,000 ohms should
follow a drying process. Please contact factory
for details on procedure if heater is under
500,000 ohms
WARNING
FIRE HAZARD
Heater should be submersed
in the fluid for proper operation and to avoid
element overheating that could result in fire or
damage of the heater.
1. Check that all connections are tight.
2. If a thermostat is provided, verify that it is operating properly
by cycling it and verifying cutout.
3. Perform an IR test prior to energization and verify that levels
are acceptable (500,000 ohms min).
4. Energize the heater and check for signs of hotspots in the
electrical connections or vessel.
5. Retorque all bolted fitting connections and all electrical
connections after 10 cycles.
6. For heaters installed in a tank, maintain a minimum of 51mm
(2’’) of liquid above the heated portion of the element or
element failure may result. Heating elements should be kept
above sediment deposits or it may overheat and shorted life
expectancy.
14. The heaters must be protected against abnormal earth
fault and earth leakage current. Depending on the electrical
power system, the following protection device must be
installed with the heater:
TT and TN Systems:
A residual current protection device with a trip setting not
exceeding 100mA. The residual current protection device
shall disconnect power supply to the heater when residual
current above the trip setting has been detected.
IT Systems:
An insulation monitoring device designed to trip when the
insulation between any phase of the electrical power supply
to ground is less than 50Ω/V.
WARNING
WARNING Low megohm on heating elements
with epoxy or hermetic seals cannot be serviced
in the field. Typical resistance values when
sealed are 1000 MΩ or greater.
E. MAINTENANCE
WARNING
WARNING Disconnect all power before servicing
the heater or heated equipment. Failure to do so
could result in personal injury and/or property
damage. All maintenance and installation should
be done by qualified personnel in compliance
with local codes.
1. Heaters stored for prolonged periods may absorb moisture.
Using a 500V DC megger (insulation resistance tester) check
the value of the insulation resistance to ground for each
circuit. Initial readings of over 500,000 ohms to ground are
normally acceptable. Should lower readings be observed,
check factory for instructions.
2. Periodically check electrical connections for tightness
and check wire insulation for any damage and replace if
necessary.
3. Remove the immersion heater periodically to inspect for
corrosion, sludge build-up and for scale removal. Do not
continue to use a heater showing visible signs of damage.
WARNING
WARNING When operating the heaters in
a closed system or vessel, system designers
must ensure that proper controls are used
to maintain the temperature and pressure at
normal levels.