Hardware Functions; Operating Display; Test Jack For Output Signal - Siemens SITRANS TW 7NG3242 Betriebsanleitung

3

Hardware functions

3.1

Operating display

The green operating indicator (5, figure 2, page 83) signals the following
operatingstates:
• no power supply
• faultless operation
• faulty operation
− Diagnostic alarm:
→
→
− Diagnostic warning
→
→
→
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
SITRANS TW
A5E00054075-05
sensor error
hardware- / firmware error
limit value exceeded /
dropped below
output saturation warning
measured value outside
sensor limits
Hardware functions
: operating indicator does not light
: operating indicator lights
: operating indicator flashes
: flashing frequency = 1Hz (priority 1)
: flashing frequency = 1Hz (priority 1)
: flashing frequency = 5Hz (priority 2)
: flashing frequency = 1Hz (priority 3)
: flashing frequency = 1Hz (priority 4)
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