KROHNE OPTITEMP TT 50 C-R EN - Manual (Page 18)

4
ELECTRICAL CONNECTIONS
18
OPTITEMP TT 50 C/R
www.krohne.com 09/2010 - 4000636502 - MA OPTITEMP TT 50 C/R R03 en
4.4 Connection diagram of in-head transmitter (Ex)
DANGER!
The Ex transmitter can be installed in potentially explosive areas of zone 0, 1 and 2. It may only
be connected to sensors that meet the requirements for "simple equipment" in EN 60079-
11:2007, section 5.7. During operations in potentially explosive areas always regard the relevant
safety instructions and especially the following items:
• The transmitter must be supplied by an intrinsically safe power supply unit or Zener barrier
placed outside of the potentially explosive area.
• The output parameters of the Ex approved Zener barrier or voltage supply and the output
parameters of the Ex approved HART unit or modem have to be less or equal than the input
parameters of the transmitter (i.e. U
i
, I
i
, P
i
, L
i
, C
i
).
• Only use an Ex approved HART ® modem.
• Observe the maximum cable lenght of the output circuit to ensure reliable HART ®
communication with this transmitter ( on page 19).
DANGER!
To enable HART
® communication, the output circuit must have an output load of at least 250 Ω.
1 Input
2 Potentially explosive area
3 Safe area
4 Output
5 Modem
6 Zener barrier or voltage supply 12…30 VDC (intrinsically safe)
7 Modem, Ex-approved
8 See section "Cable length"
INFORMATION!
The HART
® modem is connected parallel to the output load or parallel to the output of the
transmitter.
.book Page 18 Monday, September 13, 2010 5:07 PM