Vmac PREDATAIR User manual

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Installation Manual
PREDATAIR
Hydraulic Compressor
1.0 General Information ...................................................................3
1.1 Specifications and Components ...............................................3
2.0 Installation Requirements..........................................................6
2.1 Air Receiver Requirements .......................................................6
2.2 Ventilation Requirements..........................................................7
2.3 Hydraulic Requirements............................................................9
2.4 Electrical Requirements ..........................................................10
3.0 Installing the PREDATAIR .......................................................11
3.1 Mounting the Compressor.......................................................11
3.2 Connecting the Wiring.............................................................12
3.3 Speed Control .........................................................................13
4.0 Completing the Installation .....................................................16
4.1 Before Operation Checklist .....................................................16
4.2 After Engaging the Hydraulics Checklist.................................16
4.3 Setup, Performance Testing and Adjustments .......................17
5.0 Testing Ventilation ...................................................................19
5.1 Calculating Duty Cycle............................................................19
5.2 Testing the Installation ............................................................21
5.3 Analyzing the Test Results .....................................................24
6.0 Hydraulic System Data.............................................................27
6.1 Hydraulic Oil Type...................................................................27
6.2 Hydraulic Line Sizing ..............................................................28
6.3 Hydraulic System Filtration .....................................................33
6.4 Hydraulic Oil Reservoir ...........................................................34
6.5 Avoiding Cavitation .................................................................37
Ordering Parts.................................................................................38

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Document #1930150
Installation Manual for VMAC PREDATAIR Hydraulic Compressor
Changes and Revisions
Version Revision Details Revised by/date Approved Implemented
00 Original manual IB 14 Sept 2007 SM 03 Dec 2007 07 Dec 2007
Important Information
The information in this manual is intended for certified VMAC
installers who have been trained in installation procedures and for
people with mechanical trade certification who have the tools and
equipment to properly and safely perform the installation. Do not
attempt this installation if you do not have the appropriate
mechanical training, knowledge and experience.
Follow all safety precautions for mechanical work. If you have
difficulty with the installation, contact VMAC.
The VMAC warranty form is located at the back of this manual. This
warranty form must be completed and mailed or faxed to VMAC at
the time of installation for any subsequent warranty claim to be
considered valid.
To order parts, contact your VMAC dealer. Your dealer will ask for
the VMAC serial number, part number, description and quantity. To
locate your nearest dealer, call 1-800-738-8622.
Copyright 2007
All trademarks used in this manual are the property of the respective copyright holder.
The contents of this manual may not be reproduced in any form without the express
written permission of VMAC, 1333 Kipp Road, Nanaimo, BC V9X 1R3.
Printed in Canada

1.0 General Information
Read this manual before beginning the installation so that you can
understand the hydraulic, electric (Figure 2) and ventilation
requirements. This will ensure a successful installation and effective
operation of the PREDATAIR (Figure 1).
1.1 Specifications and Components
This is a flooded-lobe, rotary screw compressor (filled with VMAC
certified and approved synthetic oil) driven by a hydraulic motor.
Compression occurs when inlet air (at normal atmospheric pressure)
enters a chamber where it is trapped between the rotating rotor
lobes. A lubricated pitch line provides sealing. As the lobes mesh,
they reduce the volume of the air, compressing it to the desired
pressure.
The system has a two-stage air/oil separator. The first separation
stage consists of baffles, which perform mechanical separation. The
second stage uses a special separation element, which delivers dry
air to the outlet.
Pressure regulation is achieved with a mechanical inlet control valve
and an adjustable pressure regulator.
The compressor is protected by a paper-type replaceable air filter
and a spin-on type oil filter. Oil is removed from the delivered service
air by a coalescing separator element.
Safety features include:
•2,800 psi hydraulic pressure relief valve
•200 PSI relief valve in oil/air tank
•blow-down valve to discharge system pressure on shutdown
•temperature safety sensor in compressor and hydraulic oil
Do not disable or bypass the over-temperature
shutdown circuit. Failure of the shutdown system could
result in equipment damage, injury or death.
!
A liquid-to-air cooler maintains operating temperatures in an optimal
performance range which increases system durability and reduces
the temperature of the compressed air.
The system pressure is factory-set at 150 psi. This can be adjusted
using the display box. To reduce the pressure, use a Filter Regulator
Lubricator (FRL).
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Compressor air filter
(must have proper ventilation)
Oil cooler (inside cover,
must have proper ventilation)
Air discharge port
with check valve
Hydraulic fluid inlet
Hydraulic fluid return
Blowdown cap with
internal coalescing filter
Minimum clearance
for servicing - 6 inches
Compressor oil fill
(shipped full from
the factory)
Oil level sight glass
(make sure this can be easily
accessed for daily inspection)
Compressor oil drain
Oil filter
Cooling fan
Minimum clearance
for servicing - 6 inches
Pressure sensor
Figure 1 – System components
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REMOTE SWITCH
RED
BLK
BLUE
BLUE
OPTIONAL
HEATER
SOLENOID
WHT
BLK
RED
GRN
YELLOW
READY
WARNING
DISPLAY BOX
COMPRESSOR
INLET
VALVE
COMPRESSOR
TEMPERATURE
PROBE
SOLENOID
CONTROL
BOX
RELAY
FAN MOTOR
INSTALLER INTERFACE
RED
GRN
PPL
RED
GRN
ORG
RED
GRN
RED
WHT
ORG
PPL
PPL
ATM MINI
3A (VIOLET)
HYDRAULIC
MANIFOLD
RED
RED
ORG
WHT
BLOWDOWN CAP
SYSTEM
PRESSURE
SENSOR
AIR SEPARATOR TANK
RED, GRN, BLK
UNLOAD
SOLENOID
GRN
GRN
RED
GRN
RED
RED
SEE INSTALLATION MANUAL
FOR CONNECTION DETAILS
HYDRAULIC OIL
TEMPERATURE
PROBE
Figure 2 – System wiring
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2.0 Installation Requirements
The information in this section is very important for
proper operation of the compressor. Read these
requirements before beginning installation.
Before installing the compressor, examine the possible locations and
consider the following factors when selecting a location:
•it is convenient for making electrical, hydraulic and air
connections and does not require extensive plumbing
•hose and wire lengths will be the shortest possible and a
minimum number of 90 degree fittings will be used
•the oil level at the sight glass can be checked easily
•there will be sufficient clearance around the unit for good air
circulation and effective cooling
•it can be serviced easily without having to disconnect lines or
remove and reposition the unit
•it will be protected from excessive exposure to the elements
and possible incidental damage from other operations
•it is away from heat sources such as engines, exhaust
systems or other components that generate heat
•it is not in a location where it will be exposed to high
contamination levels, including combustible gases
•The PREDATAIR60 requires higher hydraulic flow and
pressure than a typical 30-40 CFM system. Check pump,
hose and connection ratings and requirements.
The PREDATAIR is designed to sufficiently cool the
compressor and hydraulic oil for its own use only.
Additional hydraulic oil cooling is required if other
hydraulic equipment is being used on the same circuit.
2.1 Air Receiver Requirements
A reservoir tank is recommended, particularly for
systems using the two-speed function.
The PREDATAIR uses an unloader system which minimizes fuel
burn, equipment wear, cooling load, enclosure temperature,
hydraulic temperature and noise, when compressed air is not being
used. For this unloader system to work most efficiently, and to avoid
having the compressor loading and unloading too frequently, some
air receiver volume is very beneficial.
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If the plumbing downstream from the PREDATAIR is tight (no leaks),
a 5 gallon air receiver is adequate. If you use an auxiliary air tank
with this system, the line to the auxiliary tank must be installed as
high as possible (not in the bottom of the tank) to prevent water from
clogging the line (Figure 3). Failure to observe these requirements
will result in damage to the system.
PREDATAIR Tank
Auxiliary Tank
One-way check valve
built into PREDATAIR
tank
I
nsta
ll
t
hi
s
li
ne
hi
g
h
on t
h
e
tank, not at the bottom
Figure 3 – Auxiliary tank connection
A one-way check valve is built into the PREDATAIR
tank. Do not install an additional check valve as this
may cause undesirable operations.
2.2 Ventilation Requirements
During operation, the PREDATAIR can develop
considerable heat, as much as a house furnace.
!
Proper ventilation is vital for proper operation and to
avoid damage to components.
If you are installing the compressor into a new
configuration, refer to section 5.0 Testing Ventilation for
information.
2.2.1 Top Mounting
This is the preferred mounting location. Placing the unit on top of the
service body (Figure 4) provides the best access to ambient air and
provides the best cooling. Maintain a minimum of 6” between the
sides of the compressor housing and all other solid objects
2.2.2 Enclosed Mounting
Enclosed mounting is not recommended for most
applications due to the significant heat generated.
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Mounting the PREDATAIR in an enclosure (Figure 4) will limit the
access to ambient air, restrict the escape of hot air from around
the unit and have an adverse effect on cooling. Make sure that
adequate ventilation is provided so the cooling system will
function properly (i.e. a pull-out drawer).
To p m ou n t
Enclosed mount
Figure 4 – Mounting locations
It is not possible to make absolute recommendations regarding
ventilation because of the widely differing circumstances that are
possible. Duty cycle, ambient temperature and enclosure shape
are some of the important variables.
Significant ventilation and additional cooling will be
required if the PREDATAIR is mounted in the same
enclosure as the hydraulic oil reservoir. The heat
generated during operation will continue to heat the
hydraulic oil, even with fresh, ambient air entering
the
!
cooler
Ideal ventilation will provide good airflow through the unit with no
restrictions Cool ambient air ducted to the cooler and installing an
exhaust fan to remove hot air are recommended.
If the PREDATAIR is mounted inside a service body with a door
that needs to be manually opened to provide ventilation, install a
switch on the door so that the compressor will only operate when
the door is open (Figure 5) or the pull-out drawer is extended.
Battery Relay
PREDATAIR60
R
e
m
o
t
e
s
wit
c
h
Door switch
Figure 5 – Door switch
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2.3 Hydraulic Requirements
If the compressor is being installed on a truck that does
not have a hydraulic system, you will find information
on selecting and installing hydraulic components in
section 6.0 Hydraulic System Data.
Hydraulic System Pressure will vary considerably during compressor
operation (Figure 13). The system pressure varies between 900 and
2,400 psi during normal operation.
The pump must be rated for 1,900 psi steady operation and 2,600
psi intermittent to allow an additional 200 psi for pressure drop in the
hydraulic lines (external to the PREDATAIR) during startup with cold
oil.
Compressor capacity depends on hydraulic flow.
2.3.1 PREDATAIR60
For single speed operation a minimum of 14 GPM and a maximum of
20 GPM hydraulic oil flow is required. For two speed operation, a
minimum of 12 GPM and a maximum of 22 GPM hydraulic oil flow is
required (Figure 6).
2.3.2 PREDATAIR40
For single speed operation a minimum of 9 GPM and a maximum of
14 GPM hydraulic oil flow is required. For two speed operation, a
minimum of 8 GPM and a maximum of 15 GPM hydraulic oil flow is
required (Figure 6).
Nominal Air Flow vs Hydraulic Flow
0
10
20
30
40
50
60
70
12111098 13141516171819202122
H
y
draulic Flow
(
GPM
)
Air Flow(CFM)
PREDATAIR40
PREDATAIR60
Figure 6
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These are nominal values only. Tests should be performed to
confirm that the desired CFM has been achieved due to variations in
hydraulic system efficiency, load and flow.
If the compressor is being installed on a truck that already has a
functioning hydraulic system, check the specifications for that system
to ensure that it meets minimum requirements.
The information in this manual is based on a fixed displacement
pump. Special considerations may be required for a variable
displacement pump.
2.4 Electrical Requirements
The PREDATAIR requires a steady 17 Amps @ 12 VDC to operate.
A 30 Amp fuse or circuit breaker is recommended.
To assure an un-interrupted supply of power, the ground wire should
be routed either to the negative terminal of the battery or to a
substantial, fully grounded point on the vehicle chassis, located in an
area which will provide a good ground at all times.
Power should be ignition switched through a relay to reduce the risk
of battery drain when the engine is off. Main power should be tapped
directly from the positive terminal of the battery through a relay with a
contact rating of at least 20 Amps. Using a relay allows the heavy
gauge power wire to be routed directly and permits the use of a light
(18 AWG) wire between the relay and the control switch (Figure 7).
2.4.1 Wire Size Selection
Selecting the correct wire size is vital for proper operation. If the wire
size is too small, voltage drop will be excessive and the compressor
will operate erratically. Measure the length required for both the
power wire and the ground wire, add them together and select the
correct wire size from Table 1.
Total length of Power wire PLUS Ground wire Recommended Wire Gauge
Less than 5 ft. 12AWG
5 ft. to 8 ft. 10AWG
More than 8 ft. 8AWG
Table 1 – Wire gauge size

3.0 Installing the PREDATAIR
3.1 Mounting the Compressor
1. Remove the unit from the packing. Make sure that the four
rubber isolator mounts remain fastened to the unit base.
2. Remove the two ORB plugs from the manifold on the side of the
compressor and install suitable ORB fittings to match your
connection requirements. The cold climate kit (A700146) can be
installed at this time.
Some hydraulic oil will run out when the fittings are
removed.
3. Remove the 3/4 inch NPT plug fitting from the tank and install a
suitable fitting to connect to the air delivery system.
4. Drill four 13/32 inch holes in the selected mounting location
spaced at 22 inches wide and 14 inches deep. Fasten the unit in
place using Loctite on the threads. A mounting bracket kit
(A700140) is available.
Do not mount the unit directly to the body without the
rubber insulators, as this will result in considerable
vibration and noise during operation.
5. Refer to Section 6.0 for hydraulic system recommendations. An
independent hydraulic system is recommended to simplify
installation and troubleshooting. Connect hydraulic and air hoses
to the unit. Use a shut-off valve if you have other hydraulic
devices operating within the same system.
Direction of hydraulic flow is critical. If reversed, high
pressure buildup may cause damage to the compressor
and a potential hose burst hazard.
!
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3.2 Connecting the Wiring
Battery
Fuse
+
Display box
inside cabinet
protected from
weather
PREDATAIR60
Battery
F
use or c
i
rcu
i
t
b
rea
k
er
30A PREDATAIR
see table 1 for correct wire gauge
***
*
Red
Green
Ignition-switched
relay
Figure 7
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3.2.1 Remote ON/OFF Connections
Connect the yellow remote wire on the harness coming out of the
PREDATAIR to one side of a switch or remote control relay module.
Connect the other side of the switch or relay to a chassis ground.
The PREDATAIR will turn on when the circuit between the yellow
wire and ground is completed by the switch or relay. The
PREDATAIR will turn off when the switch or relay opens the circuit.
The display box can be used to see messages, but if the system is
operated using the remote wire, the push buttons on the display box
are disabled. The PREDATAIR can be operated without a display
box by using the remote wire but messages and diagnostics will not
be available.
3.3 Speed Control
The PREDATAIR has the ability to signal for a higher engine speed
under high air demand conditions and for a lower engine speed
under low air demand conditions.
Most work trucks either have a built in electrically activated idle up
system or an after-market product may be available which will
provide this function.
It is not essential that the two speed feature be used, it is entirely
acceptable to run the PREDATAIR constantly at a fixed engine rpm
and pump GPM. There are, however, several advantages to the two
speed feature which should be considered when deciding whether to
go with two speed or single speed operation.
Two speed operation offers these advantages:
•lower fuel consumption.
•lower noise.
•lower wear rate on engine, hydraulic pump and compressor.
•greater latitude for flexible service intervals.
•better cold start behavior.
The preferred approach for speed control is to keep the hydraulic
flow as low as possible when the PTO first starts, then when the
PREDATAIR is engaged, the engine idles up for the desired
performance.
For single speed operation, the throttle would idle up to achieve the
desired CFM when power to the PREDATAIR is turned on (Figure 8).

For two speed operation, speed 1 is activated when power to the
PREDATAIR is turned on. This is set for the minimum desired CFM.
Speed 2 is connected to the purple wire and set to the maximum
desired CFM (Figure 9).
The system must be at or above the minimum hydraulic
oil flow before starting the PREDATAIR.
Always allow for efficiency loss as the hydraulic oil heats. Operate
the system for at least one hour at full load and monitor hydraulic
flow at speed 1 and speed 2 (if applicable). Adjust as required to
ensure that speed 1 flow does not drop below the minimum
requirement. A flow meter should be temporarily plumbed into the
PREDATAIR return line to confirm actual hydraulic flow. A load tester
with the load valve adjusted to zero can be used.
3.3.1 Single Speed
For single speed operation, do not use the purple wire from the
PREDATAIR wire harness. Connect a throttle control so that the
engine goes to the desired speed when power to the PREDATAIR is
turned on (Figure 8).
Red
Purple
Green
From PREDATAIR
Power circuit
Throttle control
12V input when
Power circuit is
switched on
Speed 1
Set speed 1 to achieve desired CFM
(not connected)
Figure 8 – Single speed operation
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3.3.2 Two Speed
Speed 1 This is typically set for the minimum GPM rating. The
engine stays at base idle when only the PTO is
engaged. This is desirable for cold climate start-up as it
keeps hydraulic pressure low during warm-up. A preset
throttle speed is activated when power to the
compressor is switched on to provide the minimum
GPM rating before starting the PREDATAIR (Figure 9).
Speed 2 The purple wire is used to activate a second preset
throttle speed that will provide the maximum GPM
rating (Figure 9)
Red
Purple
Green
From PREDATAIR
Power circuit
Throttle control
12V input when activation circuit is switched on
and the purple wire is grounded by the control system
Speed 1 Speed 2 Set Speed 1 to the miniumum GPM rating
Set Speed 2 to achieve the desired CFM
86
87
87A
30
85
Figure 9 – Two speed operation
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4.0 Completing the Installation
4
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ake sure that the following have been completed before operating
heck the compressor oil level. The compressor has been filled
heck the hydraulic oil level
o a final inspection to make sure that all fasteners and
heck that all hoses and wiring are secure and protected.
lock e
arm it before activating
Make su e that the following have been completed:
perate the system with an air tool for at least 1/2 hour (1 hour
heck all components once the compressor and truck engine
.1 Before Operation Checklist
M
the PREDATAIR for the first time:
C
to the correct level prior to shipping, but the oil is very clear and it
is difficult to see the level.
C
D
connections are tight.
C
4.2 After Engaging the Hydraulics Checklist
Place the truck in a safe operating position and b
!
the wheels. Ensure that there are no people around th
truck before beginning the test.
Circulate the hydraulic fluid to w
the PREDATAIR when temperatures are below -15
° C.
r
□O
preferred). If this is a new configuration or design, operate for at
least 1 hour at the expected duty cycle to confirm acceptable
CFM and temperature performance (see section 5.0 Testing
Ventilation). Check hydraulic flow to ensure that the desired
GPM is maintained.
□C
have been turned off and the system has cooled

□Check the compressor and hydraulic system oil levels after the
compressor and truck engine have been shut down and the oil
level has had time to stabilize.
4.3 Setup, Performance Testing and Adjustments
This system has been adjusted at the factory for general operation. If
your tests indicate that adjustment is necessary, refer to the owner’s
manual for specific instructions on how to adjust the system.
You can test the system operation using the tools that will be
operated by the system or you can test operations using an orifice
(Figure 10) to simulate tool use. See section 5.1, Table 3 to
determine the correct orifice size
Figure 10 – Test tool
1. Install the test tool in the air reservoir tank outlet fitting.
Make sure there are no leaks in the test tool. A reservoir
tank is recommended. The system may not idle down or
unload without a small reservoir of air or if there are
leaks in the lines or fittings.
2. Make sure that the ball valve is closed.
3. Place the manual transmission in neutral or the automatic
transmission in park and fully apply the park brake.
4. Allow the truck to run until the engine is at operating
temperature.
5. Operate the air compressor system until the oil is warm.
6. Observe the pressure gauge. Factory default pressure is
approximately 150 psi.
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7. Slowly open the ball valve on the test tool and observe the
operation. If the throttle enable wire has been connected, the
engine should idle up as the pressure drops to 120 psi.
If the air pressure drops below 100 psi, increase
hydraulic flow to bring the pressure back up. Do not
exceed specifications
8. Close the ball valve to allow the system pressure to rise. When
the control system does not sense air use for a few seconds, it
will unload the compressor. You should hear a hissing noise as
the air vents. If the air pressure doesn't drop, after approximately
another 20 seconds, the engine will idle down to the lower speed
setting.
9. After one minute (if the air pressure still hasn’t dropped) the
compressor will stop turning and the hydraulic oil will continue to
circulate through the cooler. The system will continue to monitor
hydraulic oil temperature and will run the cooling fan as required.
Once air is used and pressure drops below 120 psi, the
compressor will restart and build air pressure. The system may
restart occasionally even without air use to maintain correct
compressor operating temperatures.
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5.0 Testing Ventilation
The following procedure is recommended when a new installation
configuration is being developed. The procedure is not necessary
for repeat installations with the same configuration.
5.1 Calculating Duty Cycle
Duty cycle can be determined based on expected tool use or by
identifying the desired CFM of the system. Refer to Table 3 to
determine duty cycle from a given CFM consumption.
The rated consumption of an air tool is listed as an average based on a 25%
duty cycle. For example, a 1/2” impact might be listed by the manufacturer
as 5 CFM rather than the true consumption of 20 CFM. Do not use the
average rating in calculating duty cycle. Typical air consumption of some
pneumatic tools is:
•1/2” impact – 20 CFM
•3/4” impact – 30 CFM
•Blow-off nozzle with 0.040” orifice – 2 CFM
•Carbon arc gouger – 25 CFM
•Pneumatic hammer – 4 CFM
Determine what tools will be used, their actual CFM, and how many
minutes in an hour they will be used. Form 1 can be copied and used to
determine duty cycle. A sample calculation is shown in Table 2.
Tool Description CFM x
Operating Time
(min/hr) = CFH
x =
x =
x =
x =
x =
x =
Total CFH (Cubic Feet per Hour)
Duty Cycle = Total CFH ÷ 3600 x 100%
= ____ ÷ 3600 x 100%
= ____%
Form 1 – Duty Cycle Calculation

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Tool Description CFM x
Operating
(min/hr) = CFH
1 1” impact 40 x 5 = 200
2 1/2” impact 20 x 5 = 100
3 Blow-off nozzle 2 x 5 = 10
4 Diaphragm pump 15 x 10 = 150
x =
x =
Total CFH (Cubic Feet per Hour) 460
Duty Cycle = Total CFH ÷ 3600 x 100%
= 460 ÷ 3600 x 100%
= 13%
Table 2 – Sample calculation
Use Table 3 to find the orifice size and expected CFM based on the
calculated duty cycle.
Duty Cycle Orifice Size Drill Size Consumption
5% 0.036 #64 3 CFM
10% 0.050 #55 6 CFM
15% 0.065 #52 9 CFM
20% 0.073 #49 12 CFM
30% 0.089 #43 18 CFM
40% 0.103 #37 24 CFM
50% 0.120 #31 30 CFM
60% 0.137 #29 36 CFM
70% 0.147 #26 42 CFM
80% 0.158 #21 48 CFM
90% 0.167 #19 54 CFM
100% 0.176 #16 60 CFM
Table 3 – Orifice sizes