Altek Model 934 Milliamp Voltage Loop Calibrator Manual

16
OPERATING INSTRUCTIONS
SOURCE MODE
STORING QUIK-CHEK OUTPUTS
1) Switch to HI or LO
2) Turn the knob to desired value
3) Press the 
STORE push-button
The LCD will flash once to show that
the value was saved
If a value is in the SET position and you
want that value stored in HI or LO, press
and hold the 
STORE push-button while
moving the switch to HI or LO. The display
will flash once to indicate the value has
been stored. Then release the 
STOREpush-button.
RECALLING QUIK-CHEK OUTPUTS
Any time you...

15
OPERATING INSTRUCTIONS
SOURCE MODE
Whenever SOURCE mode is selected the word SOURCE
will appear on the LCD display. To change the output value,
turn the speed sensitive digital pot. Turning the knob slowly
will cause a gradual change in the output. A faster rate of
change will occur when the knob is turned faster. This function
operates in all three output positions (HI, SET & LO).
ALTEK 934
20.000mA
VA LV E
OR
RECEIVER I/P
30
OPERATING INSTRUCTIONS
READ FUNCTIONS
The READ functions measures the...

14
OPERATING INSTRUCTIONS
SOURCE MODE
SOURCE
1) Move the POWER switch to ON
2) Press & hold both the STORE & RESET push-buttons for 1
second to enter the SETUP mode. The word SETUP will
appear in the LCD and the words SOURCE and READ will
alternately flash. Release both push-buttons.
3) Press the 
STORE push-button. The words SETUP and
SOURCE will remain on the LCD and the previously selected
function will repeatedly flash.
4) Turn the knob (Digital-Pot) to scroll through the available
functions. Each...

13
OPERATING INSTRUCTIONS
USING ENGINEERING UNITS
8) The word SPAN and ENG.
UNIT will appear in the
bottom half of the LCD
prompting you to enter the
highest value for the range
in the units to match the
display of the instrument
being calibrated. Turn the
knob until the highest value
of your chosen range
flashes in the bottom half of
the LCD. Press the 
STOREor RESET push-button to
continue.
9) The Model 934 will now
begin operating with the
ranges and Engineering
Units you have selected. If
Engineering...

12
OPERATING INSTRUCTIONS
USING ENGINEERING UNITS
6) You are now prompted by
flashing zeros to enter the
decimal point position for the
engineering units you have
chosen. Turn the knob until
the decimal point appears in
the location to match the
resolution of the display on
the instrument you will be
calibrating (from zero to
three digits to the right of the
decimal point). Press the
STORE or RESET push-
button to continue.
7) The word ZERO and ENG.
UNIT will appear in the top
half of the LCD prompting...

11
OPERATING INSTRUCTIONS
USING ENGINEERING UNITS
3) Turn the knob (Digital pot)
to scroll through the
available functions. Each
enabled function will flash
on the LCD.“ ENG. UNIT”
will appear as a choice for
each SOURCE or READ
function. Press the 
STOREor RESET push-button to
proceed.
4) The word ZERO will appear
in the top half of the LCD
prompting you to enter the
lowest value for the range in
mA, V or mV that will be
sourced or read. Turn the
knob until the lowest value
of your chosen range
flashes...

10
OPERATING INSTRUCTIONS
USING ENGINEERING UNITS
Scale the display of the Model 934 to match the display
of the instrument being checked. Any span in mA, mV or V in
Source or Read can be scaled to display between a
maximum of -90000 to +90000 with zero to three digits to
the right of the decimal.
The previously stored Engineering units can be recalled
by using the following procedure without turning the knob.
1) Press & hold both theSTORE & RESET push-
buttons for 1 second to enter
the SETUP mode. The...

9
OPERATING INSTRUCTIONS
 RANGES
MILLIVOLTS - mV
Choose mV to display directly in millivolts DC. Use 0 to 100
millivolts to check recorder or analyzer inputs. SOURCE from
0.00 to 999.90 mVDC. In READ the 934 autoranges between
-999.90 to +999.90 millivolts and -99.990 to +99.990 VDC.
ENGINEERING UNITS - ENG. UNIT
Choose ENG. UNIT to match the display of the instrument
being calibrated (see page 10 for instructions). Any span in
mA, mV or V in Source or Read can be scaled to display a
maximum of between...

8
√
OPERATING INSTRUCTIONS
 RANGES
The selected range is displayed on the LCD by the
annunciators listed below.
MILLIAMPS - mA
Choose mA to display directly in milliamps. Display in SOURCE
and READ functions from 0.000 to 24.000 mA. In READ you
can also measure up to 52.00 mA.
PERCENT OF 4 - 20 MILLIAMPS - mA %
Choose mA % to display in percent of span for 4 - 20 mA loops.
Use with chart recorders or current trips that display in %.
0.00% 4.000 mA
25.00%8.000 mA
50.00%12.000 mA
75.00%16.000 mA
100.00%...

BOTTOM BOARD
Calibrator Enabled
(Jumper Shorted)
on
off
CAL
7
OPERATING INSTRUCTIONS
ENABLING ADDITIONAL RANGES & FUNCTIONS
The DIP switches are located in
the battery compartment. Turn the
Model 934 off and loosen the three
slotted screws and remove the battery
cover.
38
CALIBRATION PROCEDURE
SUGGESTED EQUIPMENT
1) Digital voltmeter with accuracy of ±0.003% of reading at
2V and ±0.005% of reading at 100V
Important: The required accuracy is usually found
only on meters with 71/2  or more digits
2) 100...