Kowa Seiki DIGI-VAC User manual

Kowa Seiki 4-Channel Vacuum Meter User Interface -Overview
1.0 DIGI-VAC Overview
1.1 What can the DIGI-VAC do?
The DIGI-VAC is designed to aid in the tuning of the carburetors by providing a means to accurately adjust all
carburetors to exactly the same airflow. Equal airflow in all carburetors provides the optimal conditions for proper
engine operation and power output.
The DIGI-VAC also provides a unique measurement mode whereby each carburetor is checked for any blow-back.
Blow-back is caused by a leaky or defective inlet valve or one or more leaky gaskets in the intake path.
1. Displays vacuum for each of the four input channels.
2. Display Digital RPM and…
3. Simultaneously displays RPM on analog meter
4. Stores for future recall the highest readings during the previous measurement. This is not limited to just the
specific measurements that may have been made but the maximum values for each measurement mode and
input channel of the instrument.
1.2 What’s on the Display?
The Liquid crystal display (LCD) is comprised of three separate sections.
1. Four-digit numeric display. Displays engine RPM when channel1 is connected to the engine under test.
2. Bar graphs. Four bar graphs, one for each input channel used to display vacuum and pressure
3. Function indicator arrows. Five pointers arranged around the outside edges of the display and are used to
indicate the current measurement mode is and current measurement scale.
1.3 What do the Keys do?
The DIGI-VAC has a keypad made up of four keys. An overview of the keys and their functions is provided here to
familiarize you with their general usage. A detaileddescription of the key functions and usage is found in other
sections.
POWER key
The power key provides three separate functions.
1. Power ON -Turn on the DIGI-VAC.
2. Deletes any readings stored in the HOLD memory.
3. Power + HOLD/RUN enable or disable the backlight to save power.
V-P / AVG key
This key toggles between two functions.
1. V-P mode to measure vacuum and pressure for diagnostic use.
2. AVE mode to measure vacuum only for carb balancing.
HOLD / RUN key
This key toggles between two functions.
1. HOLD mode displays the maximum measurement value achieved during the current test.
2. RUN mode displays the current measurement value as it changes up or down.
1.4 How is the front panel organized?
The DIGI-VAC front panel is separated into two parts, one on each side of the display. The left side has the low
vacuum and V-P measurement scales, while the right side has the high vacuum measurement scale. Each bar graph
is labeled along the bottom of the display with 1-2-3-4 indicating which probe it is displaying.
Along the right side of the instrument are located the four vacuum connectors. The channel associated with each
connector is marked along the right edge of the front panel.

2.0 Using the DIGI-VAC
2.1 Turning the DIGI-VAC ON/OFF
How to turn the DIGI-VAC ON.
Momentarily Depress the POWER key to turn unit ON.
How to turn the DIGI-VAC OFF.
1. The DIGI-VAC will power off automatically three minutes after the last change of any display, or…
2. It will power off automatically three minutes after the last press of any key on the keypad.
Select Measurement type, Vacuum-Pressure or AVErage vacuum.
Depress the V-P/AVE key to select the desired mode. The selected mode is indicated by an arrow in the lower left
pointing to the V-P measurement scale, or an arrow in the lower right pointing to the AVE measurement scale. This
key may be depressed at any time to change between the two measurement modes.
Measuring RPM.
The four digits at the top of the display are used to indicate RPM. Depending on the type of engine under test, the
display will display RPM correctly, 2x, or ½ actual engine RPM. If the RPM is not correctly displayed, depress the
RPM key and the correct RPM will be displayed.
HOLD / RUN selection.
Information about the current measurement can be displayed in two ways.
1. RUN mode displays the current measurement in real time. This means the various measurement displays will
change as the engine conditions change.
2. HOLD mode displays the highest reading up to the moment for each measurement active channel. These
readings will remain on the display after the engine is shut off.
HOLD data is always recorded.
It is not necessary to select the HOLD display in order to record that information. Even when the DIGI-VAC is in
the RUN mode (real time mode) the HOLD values are simultaneously being recorded. You can depress the
HOLD/RUN key at any time during or after the test to display the HOLD readings.
Clearing the HOLD memory
Select the HOLD display with the HOLD/RUN key. Depress the POWER key and the memory and display will be
cleared.
Measurement scale
The DIGI-VAC is auto ranging and does not require user intervention (switch changing) between the low and high
vacuum measurement scales. The DIGI-VAC automatically changes the measurement scale to achive the best
display resoultion.
The current scale is indicated by two arrows near the top of the display that indicate the current scale (High or Low).
1. When the left scale arrow is lighted, the low vacuum, 0 to-14 inHg scale is selected.
2. When the right scale arrow is lighted, the high vacuum 0 to -28 InHg scale is selected.

Power saver mode
The DIGI-VAC incorporates several features designed to extend the units internal battery.
1. The DIGI-VAC turns its self off if it has been inactive for the past three minutes.
2. The backlight automatically turns off after two minutes of no activity, and turns back on when any key is
depressed on the instrument
3. Battery Saver is turned on. The battery life can be greatly extended by disabling the LCD backlight.
Disabling the backlight completely provides the greatest power savings and longest possible battery life. The back
light can be re-enabled at any time. The power saver mode setting is stored in the DIGI-VAC and will remain the
same even if the instrument turns off or the battery is removed and replaced.
To reactivate the backlight function re-enable the backlight and its becomes the default.
Disable the backlight (power saver mode)…
1. Turn the DIGI-VAC on.
2. Depress and hold the POWER key
3. Touch the HOLD/RUN key.
4. Release the POWER key.
Backlight OFF is now the default, and will not turn on until re-enabled.
Re-enable the backlight (normal power mode)…
5. Turn the DIGI-VAC on.
6. Depress and hold the POWER key
7. Touch the HOLD/RUN key.
8. Release the POWER key.
Backlight ON is the default.

General Specifications
Display
High contrast Super Twisted Liquid Crystal
Size …………………………………. 3.33” x 1.00”
Resolution ………………………….. 36 segment / each bar graph
Contrast …………………………….. Fixed
Backlight …………………………… Electro Luminescent, blue/green color
Power
Internal Battery …………………….. 3V Lithium
Type ……………………………….. 2/3AA
Recommended Types …………….. Duracell DL2/3A
Electrochem 3B793 & 3B950
Panasonic CR123A
Saft 450SC & VR0450
Sanyo CR17335SE
Kodak K123L
Operating Time
Power Saver Off ………………. 32 hours
Power Saver On ……………….. 100 hours
Memory Backup Battery …………… None
Settings such as RPM selection, Power Saver mode and HOLD data remain for up to 5 years after the internal
battery is removed.
Mechanical
Size ………………………………… 2.9” x 5.4” x 1.25”
Weight, including battery …………..
Environmental
Temperature
Operating ………………………. 0C to 50C
Storage …………………………. -20C to 70C
Humidity
Operating
Storage
Altitude
Operating ……………………….. 10,000 ft
Storage ………………………….. 40,000 ft

Measurements:
Vacuum, auto ranging: Low scale: 0 to –14 InHg
High scale: 0 to –28 InHg
Vacuum / Pressure, auto-ranging: Low scale: +4 to –10 InHg
High scale: +8 to –20 InHg
RPM: (channel 1 only) Direct reading 0 to 9990 RPM
Altitude Calibration: None Required
Backlight: Best used only in low ambient light conditions.
Instrument Case: High impact nylon. Resistant to most chemicals found in engine repair
and serving areas.