Meler Macro Series, Instruction Manual

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MELTER OPERATION MA-5052-ENG MACRO SERIES MELTER MANUAL
in the connectors, the diameters of the nozzle outputs, etc.) and the adhesive
itself (its viscosity).
For safety reasons, this pressure must be discharged when the circuit exceeds
the operating value (normally with a closed circuit and the pump activated),
which makes the use of a discharge valve or a by-pass valve necessary.
This valve may be a manual adjustment valve, using a threaded screw, or
with pneumatic control, using a pressure regulator and a pressure gauge. In
the latter case, the adhesive circuit pressure has a 1:13 ratio to the pressure
displayed on the pressure gauge.
Manual valve control
To adjust the pressure with this valve model (in an approximate manner),
follow these steps:
1. Screw the spindle in clockwise, as far as possible. In this position, the
maximum pressure is 80 kg/cm
2
.
2. Gradually loosen by turning counterclockwise until reaching the
desired pressure. Each millimeter that the spindle sticks out
represents a reduction of approximately 9 kg/cm
2
.
Pneumatic valve control
To adjust the pressure with this valve model, follow these steps:
1. Unlock the pressure regulator control by pulling on it gently.
2. Turn it clockwise to increase the pressure. This will be seen reflected
on the pressure gauge located next to it.
Warning : Do not exceed 6 bar of pressure. This corresponds to 80 kg/cm
2
on
the hydraulic circuit.
Turning off the melter equipment
If you need to disconnect the melter equipment:
1. Turn off each pump control card installed in the unit.
2. Turn off the machine switch on the door of the electrical cabinet.
3. Reduce the pressure to 0 using by-pass valve in the case of pneumatic
control.
4. Disconnect the pneumatic power to the applicators and the electrical
power to the control unit programmer, if there is one.