LeeBoy 8616B, Руководство по эксплуатации, обслуживанию и запасным частям

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LeeBoy 8616B Conveyor Paver 5-15
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Figure 5-15. Electric Heat Elements
1 - Timer
2 - L-1 Circuit Breakers
3 - Power On Toggle
4 - Heat On Button
5 - Wire Junction Block
6 - L-2 Circuit Breaker
Any element lead can be plugged into any supply plug
under the heating control/distribution box. All six plugs
are equally rated.
• Each element output consists of two wires--one
connects to the L-1 circuit and the other to the L-2
circuit.
• Each breaker has two terminals--one is connected
to the main input and the other terminal to an element
output wire.
• The L-1 circuit is the left bank of element breakers.
• The L-2 circuit is the right bank of element breakers
and wired slightly different. Each leg goes from the
main L-2 power lead through a breaker, then through
one of the six contacts on the element relays.
It is these relays that “make” or “break” the circuit to
each element to start or stop the heating cycles.
When the HEAT ON button is depressed, 12VDC is
momentarily applied to this terminal to start the timer
cycle. During the timer cycle, power will not be applied
to this terminal unless the HEAT ON button is depressed
again.
There are six terminals on the timer:
• The top two left terminals are the main 12VDC input
terminals.
• The ground is on the left.
• The power is on the right.
• The top right terminal is the common terminal to the
internal timer relay that controls the heat system.
When power is applied to the input terminal, it is also
jumped to the common (or COM) terminal on the timer.
• The lower right two terminals on the timer are the
outputs of the internal timer relay.
Element Relays
There are three relays in the control box. Each relay has
two separate sets of contacts operated by one coil.
One set of contacts are the two terminals at the top left
of the relay, and the other set is at the bottom left. When
the coil is energized, both sets of contacts will close.
The element relays are 12-volt, DC-controlled with dual
contacts rated for 240VAC.
To test the relays, perform the following procedure:
1. Disconnect any wires to the relay, or completely
remove it from the control box. ( Figure 5-15) .
2. Place the leads of an ohm meter or continuity tester
across the contact terminals (2 - 4) or (6 - 8).
NOTE: Without 12VDC applied to the coil of the
relay, the contact terminals should have
no continuity through them (open). If you
do not have 12VDC applied to the coil and
the contacts are closed, your contacts are
incorrect and the relay should be replaced.
3. With the ohm meter still on the contact terminals,
apply 12VDC to the coil terminals of the relay.
4. The contact terminals should now close and show a
path for power to the electrical elements. If not, the
relay needs to be replaced.