In the previous section we have completed FOPX 605-613
and thirteen generation two now we will learn about MFPX
generation 4
pre-start checks check the EPC is correctly programmed check that the
separator is correctly assembled check the system valves power supply with new
installations particularly pay attention to the supply are the voltage and
frequency correct click the isolator on the starter box open EPC door
click on power button in top left check the air supply 6 bar is normally
required check the water supplies high or low pressure check the break is it
off check the lubricating oil for the drive this should be between half and
two-thirds of the glass before starting see your instruction manual for the type
of oil to be used starting the L cap system start the feed pump from the pump
starter watch the pressure gauge to ensure flow is established click the
pump starter switch on the heater from the EPC 400 click the button start up
the separator the ampere meter will rise to what I value click the starter listen
and observe ensure the separator is at full speed the ammeter will come down to
the normal running value you can now click the alarm accept button and step
through the list indications now the process should be started the EPC enters
the start sequence the first stage of this is parameter 50 the closing of the
bowl closing water is applied to the bowl NV 16 is activated if the alarm
accept button is pressed once at this time the display should show the timer
parameter 50 counting down according to the parameter setting if P 90 equals 1
the oil is still recirculating around the heater click alarm accept button
next is the addition of conditioning water parameter 52 this is to keep the
sludge moist and thus help with discharge this timer runs for 60 seconds
MV 10 opens and water goes into the bowl the pressure gauge in the outlet should
show a pressure of about 0.5 bah next the oil feed valve changes
position and oil is fed to the bowl this is a stabilizing period for the
transducer the bulb fills with oil and cleaned oil is discharged by the pairing
disk a back pressure is established in the clean oil outlet the operating back
pressure is set by the regulating valve midway between the delivery height
pressure which determines the minimum back pressure and the pressure required
to overflow the bowl the transducer reference is stored by the EPC 400 at
the end of this timer this timer runs for 120 seconds it is considered good
practice to check that the separator does discharge this is done by pressing
the discharge button on the EPC this will be described in the discharge
sequence at the end of the start sequence the program moves into the
separation sequence the length of the separation sequence is determined by
parameter 1 which in turn is set according to the amount of sludge in the
oil P 1 equals P 60 plus P 61 most of the time is spent in the separation
sequence unless the oil contains free water and sludge nothing special will
happen during the separation sequence until P 1 is elapsed at which point it
enters the discharge sequence the first stage of this is parameter 60 the
minimum time between the starch discharges the second stage of this is
parameter 61 the maximum time between the sludge discharges we will first
consider what happens when there is extremely low free water contamination
in the oil first part of separation sequence is parameter 60 this timer runs
for 10 minutes unless interrupted by trigger signal second part of separation
sequence is parameter 61 this timer runs for 20 minutes from less interrupted by
trigger signal at the end of this timer the controller moves into the discharge
sequence when the maximum time between this
charges p-61 has elapsed the controller starts the discharge sequence by the
addition of displacement water we will now consider what happens when there is
no amount of free water contamination in the oil during the first part of
separation sequence parameter 60 there is no change in the transducer value
this timer runs for 10 minutes during the second part of separation sequence
parameter 61 as there is some free water in the oil it will be separated from the
trigger point will be reached this time it runs for 20 minutes unless
interrupted by trigger signal when the trigger point is reached the controller
enters the discharge sequence at the beginning of p72
we will now consider what happens when there is more free water contamination
in the oil first part of separation sequence is parameter 60 this timer runs
for 10 minutes as the water fills inwards the graphical transducer value
should increase - the trigger point when the trigger point is reached the water
level in the bowl has reached the disk stack the water drain valve opens and
the water leaves the bowl slowly through the hole in the flow control disk there
is a slight drop in the oil back pressure when the water drain valve is
open there is a delay period after the trigger level has dropped below 100
percent after which the water drain valve closes if the trigger point is
reached during P 60 the opening of the drain valve is repeated at the end of
this timer the controller moves into P 61 second part of separation sequence is
parameter 61 this timer runs for 20 minutes unless interrupted by trigger
signal there is some free water in the oil this time the trigger point is
reached as the water fills inwards the graphical transducer value should
increase - the trigger point when the trigger level reaches 100 percent this
is the point at which P 61 is interrupted and the controller enters
the discharge sequence at the beginning of P 70
- when the trigger point is reached the controller enters the discharge sequence
at the beginning of p72 now go to the discharge sequence
discharge sequence at the beginning of every time discharge that is when there
is extremely low free water in the oil displacement water is added to economize
on oil losses this timer runs for 120 seconds unless interrupted by trigger
signal can v10 opens and water goes into the bowl the pressure gage in the outlet
should show a pressure of about 2.2 ma slightly higher as water is being added
as the water approaches the disk stack some water is detected by the transducer
and the trigger level starts to rise when the trigger reaches 100% the
addition of displacement water is stopped the hole opening water is then
applied if the trigger point is reached before the separation sequence timer has
elapsed then the discharge sequence starts with the opening water it is not
necessary to earn displacement water as the oil has already been displaced to
the disk stack by the free water the EPC must see the feedback signal which
indicates that a discharge has taken place this facility is only possible
with partial discharge polls the trigger point is reached this time it runs for
1.0 seconds when the pressure in the oil outlet line drops below the low alarm
setting the red LED for low pressure comes on this is the discharge feedback
signal telling the controller there has been a discharge the volume of sludge
and water ejected is approximately 70% of the volume of the sludge space the
sludge space is from the edge of the disk stack to the edges of the bowl in
the MF px system P 74 closing water is now added after 5 seconds in the next
step we are going to show P 76 conditioning water a small amount of
conditioning water is added to help with the next discharge this timer runs for
25 seconds the pressure gauge in the outlet
should now recover to 2.2 bar when water is being added the new stalled reference
value can be higher or lower than the previous reference if at any time the
actual value of the transducer moves below the stored reference than the
reference moves and stays of this value this timer runs for 30 seconds the
pressure gauge in the outlet should now recover to 2 bar the reference time is a
stabilizing period at the end of this time a new reference is taken and stored
by the EPC the trigger range is adjusted accordingly stopping sequence this is a
sequence of events which safely stops the separator initiate the sequence the
stopping sequence begins immediately after the sludge discharge sequence is
finished the controller enters the beginning of the discharge sequence this
has already been described the only difference at this time is that the
third led from the top flashes yellow this yellow LED is steady when the
sludge discharge sequence is complete displacement water is added this timeout
runs for 70 seconds MV 4:10 opens and water goes into the bowl the
recirculation valve has changed position oil is no longer being supplied to the
separator displacement water is being fed into the bowl it pushes out the oil
remaining in the bowl the motor is then stopped separator motor has been stopped
this timer runs for 180 seconds oil is recirculating stop the heater
from the EPC make sure that the oil temperature drops the break should be
applied once the EPC displays off is the temperature falling stop the feed pump
at the starter when the separator has stopped release the brake restart the
separator for 20 seconds to empty the bowl of remaining liquid gross system
valves as necessary click on the highlighted parts to get the operational
initiate a discharge temperature readout water supply pressures to the valve
block whilst most installations do not have specific pressure gauges you should
be aware that the system will malfunction if pressure is lost water
supply pressures to the valve block whilst most installations do not have
specific pressure gauges you should be aware that the system will malfunction
if pressure is lost air pressure air pressure of 6 bar is
needed to operate the valve actuators oil temperature this can either be
checked on the EPC if a pt100 sensor is fitted or on a local thermometer gearbox
or spindle drive oil level gearbox or spindle drive oil level flow indicator
it is a simple indicator and not a flow meter this gives an indication of the
flow rate of the system
backpressure the minimum value of this back pressure will be dependent upon the
delivery height the operating back pressure is set by the regulating valve
midway between the delivery flight pressure and the pressure required to
overflow the bowl some early systems were supplied with a flow switch instead
of pressure switches in such cases there may not be a pressure gauge or
regulating valve motor current