Brookfield Temperature Controller, Model 75 - Manual (Page 10)

Brookfield Engineering Labs., Inc. Page 10 Manual No. M/98-205-A0100
VI.2 Thermosel Overheat Error
If the sensor becomes dislodged or is left out of the Thermo Container or if the Thermo Container
coils become “open”, and the Model 75 Controller is not sensing a temperature rise while dis-
pensing power to the Thermo Container, it will display the following message after approxi-
mately a 3-minute delay:
e В В
The Model 75 Controller will stop control and will stay in this state until the problem is corrected.
The only way to correct this error is to turn off the Model 75 Controller and then turn it back on.
VI.3 High/Low Temperature Limit Error
If a temperature outside of the Temperature Controllers high or low temperature limits is de-
tected, either of the two messages
- Lo Lo Lo Lo Lo - or - HI HI HI HI HI - will be displayed. The Model 75 Controller will
stop control and will stay in this state until the problem is corrected. Once corrected, the unit will
return to viewing the controlled temperature.
VII. TROUBLESHOOTING
In the event that the Model 75 Controller does not appear to be working, disconnect the unit from
the power source (mains) and check the power fuses (located in a removable section of the power
input block) to determine whether they are still functional. Refer to Figure 1, Section III - use
screwdriver to remove fuse holder.
The power fuses protect the controller electronics. These fuses (Brookfield Part No. HT-98H) are
3A/ 250V fast blow Littlefuse type 3AG 312.003 or equivalent.
The Model 75 Controller is designed to require a minimum amount of user maintenance. There
are no user serviceable parts inside the unit. In the event of difficulties with the product, con-
tact Brookfield Engineering Laboratories or its authorized representative. Please have the serial
number of the unit available (the serial number is indicated on a label on the bottom of the
controller).