VEGA VEGACAL 67 4 … 20 mA_HART - two-wire User Manual
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10 Supplement
VEGACAL 67 • 4 … 20 mA/HART - two-wire
31758-EN-130917
1000
750
500
250
12
18
16
14
20
22
24
26
28
30
32
34
36
Ω
V
4
1
2
3
Fig. 23: Voltage diagram
1 HART load
2 Voltage limit EEx-ia instrument
3 Voltage limit non-Ex/Ex-d instrument
4 Operating voltage
Operating voltage with illuminated display and adjustment module
Ʋ Non-Ex instrument
20 … 36 V DC
Ʋ EEx-ia instrument
20 … 30 V DC
Ʋ EEx-d-ia instrument
20 … 36 V DC
Permissible residual ripple
Ʋ < 100 Hz
U
ss
< 1 V
Ʋ 100 Hz … 10 kHz
U
ss
< 10 mV
Load
see diagram
Electrical protective measures
Protection, depending on housing version
Ʋ Plastic housing
IP 66/IP 67
Ʋ Aluminium housing, stainless steel
housing - investment casting, stain-
less steel housing - electro-polished
IP 66/IP 68 (0.2 bar)
3)
Ʋ Aluminium and stainless housing, in-
vestment casting (optionally available)
IP 66/IP 68 (1 bar)
Overvoltage category
III
Protection class
II
3)
A suitable cable is the prerequisite for maintaining the protection rating.