Sterlco M2B, Руководство пользователя

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Field Calibration
All Sterlco controllers are pre-calibrated at the factory. Due to the design of
our input circuitry, the factory calibration should be valid for the life of the
instrument. In the event recalibration is warranted, Sterlco recommends
verifying input calibration specifications every twelve (12) months. Follow
the calibration procedures outlined in your controller manual.
Audit Temperature
Inputs
To audit the temperature probes for accuracy the following procedure
should be followed:
Materials supplied by user
1. Input Signal testing
a. Millivolt Runup (MVR) with an output impedance of 100 ohms or
less. Accuracy should be ± 1% or better.
b. Resistance decade box (RD) with an accuracy of ± 1% or better.
c. Frequency counter with an accuracy of ± 1% or better (0 to 2.5K mm.
range).
d. Frequency generator capable of 50 to 200 Hz.
2. 4-1/2 Digit Digital Multimeter (DVM) with an accuracy of ± 0.05% or
better.
3. Ambient Temperature Indicator with an accuracy of ± 0.05% or better.
4. Assortment of test leads.
Procedure
1. Power up Instrument and allow the M2B to warm up for 1 hour.
2. Hold the ENTER and UP Arrow keys for 5 seconds. The Menu will enter
the SECURE MENU. The displays will read “ ” and “
. .. .
”. If not, set the
right display to “
"" "" "" """ "" "
’, and press ENTER. The right display should blink
and return to “
. .. .
”. Press the INDEX key until you see “ ” and change
it from “ ” to “ ” and press ENTER. INDEX to “
) ) ) )# ## #
” and change it
from “ ” to “ ” and press ENTER.
3. Press the INDEX key until you reach “ ”. Use the UP and DOWN
arrow keys until “
+++
“shows in the right display. Press ENTER, and the
two left digits of the left display will read “
) ) ) )
” (See Figure-3).
This is CAL 0. Place the RTD connector into slot D (see Figure-4).
Adjust the decade box to 99.114 ohms. The calibration value of the M2B
should be between 18CA to 22CF (in hexadecimal - see Table 1). Press
the ENTER and DOWN arrow keys if the value is within the acceptable
range.
Figure-3
∆
P
S P
S
P
No
Yes
S P
S
Attach decade box
P
P
To Accept
P
To Accept
Repeat for 2c, 3c, 4c, 5c,
6c, 7c, 8c, 9c, ac, bc
RUN
Calibration #
Calibration Value (Hexadecimal, 0-9, A-F)