Development and research of flexible fabric electric heaters

RESULTS AND DISCUSSION 
Thus, the difference is R
2
th
electr.
-R
4
th
electr. 
represents the total contact resistance. The obtained averaged results are 
presented in table 1. Dynamics of changes in electrical resistance of electrically conductive fabric. 
TABLE 1. Changes in the electrical resistance of conductive fabric 
№ 
Time, 
month 
Electrical resistance, KOhm 
R
2
th
 
- electrode 
R
4
th
 - electrode 
R
c
=R
2
th
 -R
4
th
 
(Rcontact) 
1 
0 
72,4 
67,2 
5,2 
2 
0,5 
80,6 
75,2 
5,4 
3 
1,0 
89,0 
83,3 
5,7 
4 
1,5 
92,3 
86,1 
6,2 
5 
2,0 
96,6 
90 
6,2 
6 
3,0 
98,1 
91,9 
6,2 
7 
4,0 
101,0 
94,5 
6,5 
8 
5,0 
102,7 
95,7 
7,0 
R
8
/R
1 
1,44 
1,43 
1,67 
Figure 5 shows the dynamics of changes in the electrical resistance of electrically conductive fabric. 
1-2
th
electrode measurement method; 
2-4
th
electrode measuring method; 
3-contact resistance. 
FIGURE 5. Dynamics of changes in electrical resistance electric heating cloth
 
The analysis of the obtained curves in Fig. 5 indicates that after removing the fabric from the weaving machine 
with the passage of time, the electrical resistance of the fabric increases. In parallel, an increase in contact resistance 
is observed. The greatest increase in resistance occurs during the first month of testing. 
The increase in the electrical resistance of the fabric over time is due to some shrinkage of the fabric along the 
weft. In this case, the electrically conductive weft threads, consisting of a mixture of cotton and electrically conductive 
fibers, change their structure. It should be noted that the electrical conductivity of such a thread depends on the degree 
of its tension. When a certain load is applied to the thread in the longitudinal direction and its stretching, its electrical 
resistance decreases. This can be explained by some straightening and convergence of the electrically conductive 
filaments in the yarn to form a less defective electrically conductive structure. It should be noted that this phenomenon 
is reversible and that when the load is removed, the electrical resistance takes on its original value. Obviously, the 
shrinkage of the weft threads of the fabric, after removing it from the weaving machine, leads to some misorientation 
of the electrically conductive fibers, which entails a violation of the contact between them, as well as between the 
microwires of the electrodes and the weft threads. 
0
20
40
60
80
100
120
1
2
3
4
5
6
7
8
Ele
ctric
al resistanc
e, kOm
Time, month
1
2
3
030006-5

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