BRUEL & KJAER System V - Brief Description

B & K Exc it er Head Ty pes
4811
4812
4813
4814 4815
Force,
with 48 01
N (Ibf ) 370 (85)
445 (100)
445 (100)
370 (85)
370 (85)
Force,
with 4805
and cooling
N (Ibf)
248 (56)
310 (70)
283 (64) 267 (60) 267 (60)
Force,
with 48 05,
no cooling
N (l
bf) 124 (28)
155 (35) 142 (3
2) 133 (30) 133 (30)
Moving Element
Ma ss
Displacement
Limit
Resonant
Frequency
Mounting Point
Locations
kg (lb)
mm (in)
Hz
Circle,
Diameter
mm (in)
Square,
Side
mm (in)
0,18 (0,4)
13
(0,5)
8500
50,8
(0,2)
35,9
(1,414)
0,45
(1,0)
13 (0,5)
7200
76,2
(3,0)
53,9
(2,13)
0,79
(1 ,6)
13 (0,5)
5400
114,3
(4,5)
80,8
(3,18)
0,23 (0,5)
25 (1,0)
64
00
Threaded
hole in
center
of
19 mm
(0,75)
diamet
er
tab le
0,32 (0,7)
13 (0,5)
10000
Reference
accel erometer
Table 3. 1. V System Exciter Heads
Heads when connected to the 4801 Body, and when connected to the 4805 Body with
and without cooling . This force is the force F described in Section 3.1 .
T
he fourth line lists the mass of the moving elements . Exciter Heads 4811, 4814 and
4815 are wound with aluminum wire and 4812 and 4813 with copper wire . The copper
winding permits greater current flow per cross-sectional area and therefore greater force .
Use
of the aluminum winding lightens the total moving element weight . 3 .3
The fifth line lists the available peak-to-peak displacement. A displacement of 13 mm
(0 ,5 in) is adequate for almost all environmental vibration testing and calibration applica-
tions . The larger displacement of the 4814 is useful when testing structures or modeis.
3.3
The sixth line lists the resonant frequencies of the moving elements . For environmental
vibration testing and calibration applications, operation below the resonant frequency
provides low distortion and low cross motion . Although operation at frequencies up to
100 kHz is possible, the available force is considerably reduced .
Exciter Heads 4811 , 48 12 and 4813 have a centre m ountin g insert and four equally
spaced outer inserts . Line seven gives both the dia me ter of the circle formed by the four
outer inserts and the side of the equivalent square .
3. 2 . 2. Brie f D escription
The High g Head Type 4811 has an 380 N (85 Ibf) force rating, a light-weight moving
element and high resonant frequency . It is especially weil suited to the environmental vi-
bration testing of small objects, either to very high vibratory acceleration levels or to high
freq uencies .
The Big Table Head Type
4813 has a 445 N (100 Ibf) force rating, a large, stift table, and
14