Instruction manual

SITRANS TW

A5E00054075-05

Hardware functions

3 Hardware functions

3.1 Operating display

The green operating indicator (5, figure 2, page 83) signals the following

operatingstates:

If several errors occur simultaneously, flashing follows the given order of priority

(priority 1 = highest priority)

3.2 Test jack for output signal

• The test socket (6, figure 2, page 83) is used to check the 0/4 ... 20 mA current

with a measuring instrument at current output. The connection is made by 2 mm

test jack plugs. The voltage drop at the ammeter may not exceed 0.3V at 23 mA

output current.

• The test jack has no function for voltage output.

• If the analog output is in the current output 0 ... 20 mA mode or current output

0 ... 10V mode, the test jack must be bridged at 0 mA or at 0V for correct HART

communication. A suitable short-circuit connector can be ordered as an acces-

sory as follows:

− Add the suffix S01 to the order number of the SITRANS TW or

− order as accessory with order number 7NG3092-8AP

• no power supply : operating indicator does not light

• faultless operation

: operating indicator lights

• faulty operation : operating indicator flashes

− Diagnostic alarm:

→ sensor error : flashing frequency = 1Hz (priority 1)

→ hardware- / firmware error : flashing frequency = 1Hz (priority 1)

− Diagnostic warning

→ limit value exceeded /

dropped below : flashing frequency = 5Hz (priority 2)

→ output saturation warning : flashing frequency = 1Hz (priority 3)

→ measured value outside

sensor limits : flashing frequency = 1Hz (priority 4)