Kobold MAS Series, Инструкция по эксплуатации

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MAS Instruction Manual
Page 21
This completes the calibration procedure. To adjust linearity, go to
STEP 4.
STEP 4 A
DJUSTING
L
INEARITY
: First gain access to the printed
circuit board inside the MAS enclosure by using the procedure
described in Section 2.5.3, OEM E
LECTRICAL
C
ONNECTIONS
. Orient
the meter so that the component side of the circuit board is facing
you. Plug in the meter and allow it to warm up for at least 15
minutes.
STEP 5 Z
ERO
A
DJUST
: Connect a voltmeter to the meter output pins
and adjust the zero potentiometer (R5) for zero volts at zero flow (4
mA for 4-20 mA outputs).
___________________________________________________________________________________
INC. DEC. INC. DEC.
_________________________________________________________________________________
J1 0 0 0 J1 [XXXXX] 0 Adjust R25 (50%)
J2 0 0 0 J2 0 [XXXXX] Adjust R27 (75%)
J3 0 0 0 J3 [XXXXX] 0 Adjust R29 (100%)
Linearizer Jumper Array Jumpers Installed
_________________________________________________________________
STEP 6 C
ALIBRATE
25%: Use the calibration standard to set a flow
rate of 25% of full scale. Adjust the span potentiometer (R21) for
1.25 volts (8 mA for 4-20 mA outputs) at the output of the meter.
STEP 7 C
ALIBRATE
50%: Increase the flow rate to 50% of full scale.
If the output is within
±
100 mV, no adjustment is necessary. If the
output is beyond these limits, install a jumper block at J1 in the
appropriate position (increment (INC.) or decrement (DEC.); see
Figure 5-1) and adjust R25 for the proper reading.
STEP 8 C
ALIBRATE
75%
AND
100%: Set the flow to 75% of full scale.
If the output is outside the limits set in STEP 7, install a jumper
block in J2 in the proper location and adjust R27 for the correct
reading. Repeat this procedure for 100% flow, using J3 and R9 if
necessary.
NOTE: If the curve being linearized is not monotonic (e.g., jumpers
are in both increment and decrement positions), repeat STEPS 6
through 8 at least one more time.
Figure 5-1
Linearizer Jumper Array