Graco DynaMite 25D100, Instructions - Parts Manual

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Operation
3A5311D 11
Adjust the Low Level Switch
The low level switches (D) are set at the factory. How
ever, you may need to make adjustments to them based
on your specific application and the material you are
using. Follow these steps and refer to Figure 6 to make
adjustments.
1. Let the supply pump dispense material to the
desired low level of material remaining in the pail.
NOTE: The low level should be as close as possible to
the point before the pump would start to run away.
2. Loosen the two low level switch screws enough to
be able to slide the low level switch up and down.
3. Adjust the low level switch and bracket so that the
switch activates when it comes into contact with the
supply pump’s air cylinder mounting plate.
4. Tighten the two screws to secure the switch and
bracket at that position.
5. Repeat steps 1 through 4 for the other supply pump.
Light Tower Operation
This process of switching from one supply pump to
another is controlled by the low level switch (D) on each
supply pump. This switch is triggered when the material
in the pump reaches its low level. See
Adjust the Low
Level Switch .
When the system activates the low level switch and
actuates the other pump, the light tower (C) signals the
operator that it is time to replace the pail of material.
Replacing a Material Pail
When the light tower signal is red, it is time to replace
one of the pails.
1. Turn the bypass valve control (H) to the ON position
on the non-active supply pump with the empty pail.
2. Replace the pail. Refer to DynaMite 190 Extruder
Instructions - Parts , manual 308302.
3. Turn the bypass valve control (H) to its OFF posi
tion.
The light tower signal returns to green and the
non-active supply pump is now ready when the active
supply pump reaches a low level.
F
IG
. 6: Low Level Switch Adjustment
Low Level
Low Level
Air Cylinder
Mounting Plate
Switch
Bracket
Switch Screws
Bracket View
Switch View
Light Tower Signal
Green
Both Supply pumps have material and are
ready or are actively pumping.
Red
One or both of the supply pumps has
reached the low level limit. Replace the pail
as soon as possible.
NOTICE
The tandem supply system does not automati
cally stop pumping if both pails reach low level; it
continues to pump until the active supply pump
is empty.
When the red light is on, make sure you
replace the empty pail before the material reaches its
low limit in the active pail. If the non-active supply
pump pail is not replaced, the active pump continues
to accelerate, damaging the pump and possibly
inducing air into the material lines.