Dwyer Instruments MTL7700 Series, Инструкция по эксплуатации

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14 INM7700-6 Jan 2010
BARRIER DATA MULTIMETER TESTS CONSTANT-CURRENT TESTS
MTL Safety End-to-end Diode Diode Terminal Terminal
model Description Resistance Test Test Voltage Voltage
No.
Ω Ω
+ve -ve @ 10
μμ
A @ 20mA
V
Ω Ω
mA Min Max Min Max Min Max
7710+ 10 50 200 62 75
∞
Vf
z
x 1 6 9.5 6.6 9.7
7715+ 15 100 150 110 119
∞
Vf
z
x 1 12 13.6 12.4 13.7
7715P+ 15 50 291 59 64
∞
Vf
z
x 1 12.6 13.3 13 13.4
7722+ 22 150 147 159 174
∞
Vf
z
x 2 19.6 20.9 19.7 21.1
7728+ 28 300 93 311 333
∞
Vf
z
x 2 25.9 26.5 26 26.7
7728- 28 300 93 311 333 Vf
z
x 2
∞
25.9 26.5 26 26.7
7728P+ 28 237 119 241 252
∞
Vf
z
x 3 24.9 25.5 25 25.6
7729P+ 28 164 170 171 184
∞
Vf
z
x 3 24.9 25.5 25 25.6
8.4 Test tables for passive barriers
Tables 4 to 10 detail the tests for all MTL7700 Series ‘passive’ barriers. In the ‘diode test’ columns, the figures adjacent to the diode description
indicate the number of forward-biased diodes used in the barrier chain. Using the multimeter diode test function and knowing the diode voltage
drop figures (approximately 0.6V for each Zener diode and 0.3V for each Schottky diode), the expected reading across the diode chain can
be determined.
BARRIER DATA MULTIMETER TESTS CONSTANT-CURRENT TESTS
MTL Safety End-to-end Diode Diode Terminal Terminal
model Description Resistance Test Test Voltage Voltage
No.
Ω Ω
+ve -ve @ 10
μμ
A @ 20mA
V
Ω Ω
mA Min Max Min Max Min Max
7758+ 7.5 10 750 14 17
∞
Vf
z
x 1 6 6.9 6.6 7
7758- 7.5 10 750 14 17
∞
Vf
z
x 1 6 6.9 6.6 7
7764+ 12 1k 12 1010 1050
∞
Vf
z
x 1 10 11.4 10.5 11.6
7767+ 15 100 150 110 119
∞
Vf
z
x 1 12 13.6 12.4 13.7
7779+ 28 300 93 311 333
∞
Vf
z
x 2 25.9 26.3 26 26.5
7796+ 26 300 87 311 333
∞
Vf
z
x 2 23.9 24.4 24 24.6
7796+ (ch2) 20 390 51 401 428
∞
Vf
z
x 2 18.3 18.8 18.4 19
7796- 26 300 87 311 333 Vf
z
x 2
∞
23.9 24.4 24 24.6
7796- (ch2) 20 390 51 401 428 Vf
z
x 2
∞
18.3 18.8 18.4 19
7788+ 28 300 93 311 333
∞
Vf
z
x 2 25.9 26.4 26 26.6
7788+ (ch2) 10 50 200 62 75
∞
Vf
z
x 1 6 9.5 6.6 9.7
7788R+ 28 300 93 311 333
∞
Vf
z
x 2 25.9 26.4 26 26.6
7788R+ (ch2) 10 50 200 62 75 V
r
V
r
0 0 6.2 6.8
Table 4: Single channel polarised barriers
Table 5: Dual channel polarised barriers
Note: Vf
z
is the voltage dropped by a forward biased zener diode - 0.6V typically
V
r
is the voltage dropped by the sense and current limit resistors - 3.2V for a typical 1mA test current