Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

SITRANS P320 NOT RESPONDING

Created by: SMAX_1996 at: 10/11/2024 8:37 PM (5 Replies)

Rating (0)

Thanks 0

6 Entries

10/11/2024 8:37 PM	Rate (0)
SMAX_1996 Member Joined: 1/19/2022 Last visit: 11/2/2024 Posts: 5 Rating: (0)	Hello all, I'm currently working on a steam project where we're using a Siemens P320 differential pressure transmitter. We've installed the DP transmitter to measure up to a maximum of 1 bar for our process. However, when we follow the calibration procedure as outlined in the Siemens manual, the transmitter won't go to zero and stays fixed at 2 bar, even after opening the drain valves. I need to know how to get sure if the sensor is damaged or we just missing somthing form SIEMENS ? Has anyone encountered a similar issue or have suggestions on how to resolve this? https://support.industry.siemens.com/cs/de/de/view/109758474/112785759371 Attachment Capture d’écran.png (45 Downloads)
	Last edited by: Moderator_Lan at: 10/14/2024 09:08:31 link optimized
Suggestion To thank Quote Answer

10/12/2024 3:13 PM	Rate (0)
danw Gold Expert Joined: 3/28/2010 Last visit: 11/8/2024 Posts: 1074 Rating: (214)	I suggest using parameters 02 and 03, "Set Lower Range Value" and "Set Upper Range value", (meaning by manual entry of numbers) instead of using parameters 08 and 09, which senses and uses the applied pressure as the LRV or URV value. 02 LRV = 0.0 bar 03 URV = 1.0 bar? 2.0 bar? Start with getting a zero reading when pressures are blocked and equalizer valve is opened: block valves (3) and (4) are closed and the equalizer valve (2) is opened. Should read zero pressure, 4.0mA The zero trim, parameter 07 can be used to trim a slight offset due to mounting offset. Don't cook the transmitter by having draining the impulse lines and letting steam get to the transmitter through open block valves. The transmitter sensors cannot take the high temperature of steam.

Suggestion To thank Quote Answer

10/12/2024 5:02 PM	Rate (0)
SMAX_1996 Member Joined: 1/19/2022 Last visit: 11/2/2024 Posts: 5 Rating: (0)	Thank you for the information, at that point when we block valves (3) and (4) and opening the equalizer valve (2) the sensor didn't give 0 bar, he stays at 2 bar, also we tried to reset it but he gave me that message "FAILED".

Suggestion To thank Quote Answer

10/12/2024 6:33 PM	Rate (0)
danw Gold Expert Joined: 3/28/2010 Last visit: 11/8/2024 Posts: 1074 Rating: (214)	With both block valves closed and the equalizer valve open, the differential pressure has to be zero bar (plus or minus some minor installation offset) Even if the high side block valve leaks (low side block valve closed) with the equalizer valve open, then high side pressure would be applied to both sides equally, which would be 'seen' as zero bar differential pressure. Even if the low side block valve leaks (high side block valve closed) with the equalizer valve open, then low side pressure would be applied to both sides equally, which would be 'seen' as zero bar differential pressure The only way I can imagine that a transmitter could 'see' any applied pressure when the block valves are closed and the equalizer valve is open is when the equalizer valve is so blocked that opening the valve does not open its equalizing passage and the pressures on either side do not equilibrate (become the same pressure which is zero differential pressure). I have seen 3 valve manifolds get so blocked with rust, scale, dirt and crud that one or more valves could be operated but the associated port was blocked. Is the pressure you report, 2 bar, the reading in the digital display or are you interpreting 2 bar the 4-20mA output signal (20mA)? Is the steam line pressure anywhere near 2 bar when doing the testing? Which 'reset' function are you doing?

Suggestion To thank Quote Answer

10/13/2024 4:54 PM	Rate (0)
SMAX_1996 Member Joined: 1/19/2022 Last visit: 11/2/2024 Posts: 5 Rating: (0)	- Yes we got 2 bar in the digital display permanently, - The steam line range from 3 bar to 10 bar, - I was talking about the parameter 07 : Zero point adjustement.

Suggestion To thank Quote Answer

10/14/2024 1:34 PM	Rate (0)
danw Gold Expert Joined: 3/28/2010 Last visit: 11/8/2024 Posts: 1074 Rating: (214)	You do have some kind of orifice plate or DP flow element in the steam line, right? You are attempting to measure flow, not line pressure, right? What is the max DP the flow element is supposed to develop at maximum flow rate?

Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on