Table of Contents
Advertisement
CHAPTER 1: SYSTEM DESCRIPTION
significant bit in the 8, 4, 2, 1 BCD code format. A, B, C, and D are the data digits; H is the MP4
Failure Code.
When the footswitch is actuated, a +14 volt, 10 millisecond Print - Data Stable pulse appears on pin 29.
The MP4 can be inhibited from making another test by placing a +15 volt BUSY signal on pin 26. The
data on the BCD outputs are reset to zero within 10 ms after the end of the Data Stable pulse. The MP4
Failure Code Digits, pins 35 to 38, will change from zero as soon as one of the End of Test Conditions
occurs.
Signal
Ground
Busy Input
Ground
Print-Data stable
Units
Decimal Point
Decimal Point
A1
A4, Ground
Beam Drive Module
The MP4 Beam Drive Module contains a servomotor which moves the beam arm assembly vertically
within low friction, self compensating, linear ball bearing races. Within the Beam Drive Module is a
precision potentiometer that accurately tracks the motion of the beam arm and transmits this information
back to the Electronic Control Unit. The beam arm contains five sets of mounting holes which allow the
beam height to be moved 1 inch in ¼-inch increments.
Beam Module – The beam module contains a lamp housing and a cantilevered beam that is gauged with
high output semiconductor strain gauges to measure the applied force. The output of the strain gauges is
applied to a preamplifier designed to reduce susceptibility to electrical noise. The design is such that
any beam module can be installed on any MP4 without re-calibration. Each beam, upon installation,
automatically changes the location of the decimal point and modifies the units of the PEAK FORCE
display, if necessary. The beam housing contains two dowel pins that allow easy mounting in one of
five sets of holes in the beam arm. The housing is held on the arm with a thumbscrew. Two electrical
connectors are used, one carries the output data from the beam and the other carries power to the lamp
housing. The front of the beam housing slides out to allow access to the front of the beam to facilitate
installation of the hook assembly.
Beam – The beam is a low-mass, cantilevered beam with relatively large compliance. The deflection for
full-scale output is 0.2 inch, with 20% over-range allowed in the Destruct Mode. The compliance of the
beam allows measurements that are essentially free from the influence of normal shock and vibration.
The tip of each beam is designed to accept a hook.
Model B10, B100, B1000 MIL-STD Beams - The design of the MP4 hook assembly insures the
accuracy of the measuring system. Because of constraints imposed by MIL-STD-883B and 883C, the
1-4
Table 1-2. Data Output Connector, J7, Signals
Pin
1
A8, Ground
26
B1
28
B2
29
B4
4
B8
2
C1
3
C2
22
C4
24
C8
®
MICROPULL
IV WIRE BOND PULL TESTER
Signal
Pin
25
D2
47
D4
48
D8
49
H1, Failure Code
50
H2
18
H4
19
H8
20
I2, Ground
21
I1,4,8 Logical 1
Signal
Pin
44
45
46
35
36
37
38
7
6,8,9
990-180
Hide quick links:
Advertisement
Table of Contents
