Dwyer MTL7787 - Manual (Page 20)

16 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 μμA @ 20mA
V Ω Ω mA Min Max Min Max Min Max
7787+ 28 300 93 311 333 ∞ Vf
z
x 2 26.6 27.4 26.7 27.6
7787+ (ch2) 28 — — ∞ (+)
0.9V + 26
∞ Vf
z
x 2 26.6 27.4 26.7 27.6
7787P+ 28 237 119 241 253 ∞ Vf
z
x 3 26.4 27.4 26.5 27.6
7787P+ (ch2) 28 — — ∞ (+)
0.9V + 26
∞ Vf
z
x 2 26.6 27.4 26.7 27.6
7789+ 38 300 93 614 651 ∞ Vf
z
x 2 26.6 27.4 26.7 27.6
7789+ (ch2) 28 — — ∞ (+)
0.9V + 26
∞ Vf
z
x 2 26.6 27.4 26.7 27.6
Table 10: Diode return barriers
Note: Vf
z
is the voltage dropped by a forward biased zener diode - 0.6V typically