Stirring; Power - Fluke 6050H User Manual

Because salt is solid at room temperature special procedures are required in
using the bath with salt. Before filling the bath with solid salt disconnect the
stirring motor to prevent it from being damaged. (See the Stir Mode Select
section.)
Never allow the stir motor to run with solid material in the bath.
Restraining the motor from turning may over-heat and damage
the motor. Use HIGH heat (Heater Switch) and "LO" Heat Up
Power with solid salt. A Fast Start Heater Model 2024 may be
used to aid in the melting of solid salt. See the Stir Mode Select
section.
Solid salt has poor thermal conductivity. The 6050H bath uses a special "soft
start" program to prevent the heaters from being overheated until the salt is
completely molten. This program controls the heater duty cycle at 25 % until the
bath temperature reaches 200 °C. To allow the bath to control below 200 °C the
soft start feature must be deactivated (see the Stir Mode Select section, Stir Set-
point section, and Heat Up Power section.)
Salt is supplied in a pink granular form. Fill the bath gradually as the salt heats
and melts. Because of the heat required to melt the salt this is a slow process
and may take 10 hours or more. Fill the bath until the liquid is a few inches below
the lid. The level will rise as much as two inches as it is heated to the upper
temperature limit.

Stirring

Stirring of the bath fluid is very important for stable temperature control. The fluid
must be mixed well for good temperature uniformity and fast controller response.
The stirrer is precisely adjusted for optimum performance. When the salt in the
bath is solid, it is very important that the stirrer power be disconnected until the
salt melts. Otherwise, the stirrer will likely over-heat and be damaged.

Power

Power to the bath is provided by an AC mains supply. See the Specifications
section for power details.
to prevent switching spikes from being transmitted to other equipment
To turn on the bath switch the control panel power switch to the ON position. The
stirring motor will turn on, the LED display will begin to show the bath
temperature, and the heater will turn on or off until the bath temperature reaches
the programmed set-point.
When powered on the control panel display briefly shows a four digit number.
This number indicates the number of times power has been applied to the bath.
Also briefly displayed is data which indicates the controller hardware
configuration. This data is used in some circumstances for diagnostic purposes.
WCaution
See Figure 5. Power to the bath passes through a filter
Calibration Bath
General Operation
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