Vitronics Soltec XPM3m, Техническое справочное руководство

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Technical Reference Manual-XPM3m Revision Date: August 2014
HEATER CELL OVER-TEMPERATURE SWITCHES
Heater cell over-temperature switches are:

Standard, (installed on all ovens)

An option, (NOT installed on all ovens)
DESECRIPTION:
Each heating cell is equipped with a bimetallic over-temperature switch mounted on the backside of the heater
panel. When the cell temperature exceeds the switch temperature, the internal contacts open. This will interrupt
the 3- phase power to the heaters, and a signal is sent to the Oven Controller indicating an "over-temperature"
condition. This will generate an IAS alert alarm message.
This system generates only an IAS alert alarm message and will not indicate the cell location that generated the
alarm. The faulty cell must be found by diagnostically testing the functions of the cell over-temperature switches,
looking for either continuity (machine power removed) or voltage loss across the switch.
On the back (top / bottom side) of each heater cell is a terminal block assembly.
Check for either continuity or +24 VDC between terminals 24-1 and 24-2. To read continuity machine power must
be completely disconnected.
To read voltage place the positive lead in terminal 24-1 and the negative lead in ground to verify input voltage to the
switch. If input voltage is present, then move the positive lead to terminal 24-2. If there is no voltage present, the
switch is open. If the switch continuity or voltage checks are good, then move on to the next switch. Is it easiest to
start at the last heat zone on the top and then divide the machine in half for each subsequent check. If the last top
heat zone switch checks good, move directly to the bottom heat cells.