Rosemont 3051 Level Transmitter.

I know this may be a little off topic, but Im having a little issue with a Rosemont level transmitter. The only info I have on the device is when I open the end of it. It says :

Model 3051 / 3001 Electronics
Hart(R) Output 4-20ma

Ive always just removed the cover for the SPAN and ZERO buttons and pushed the SPAN button when the level on a sump has gotten off, and I want to adjust the full point.

Today, someone tried to adjust it for me, and pressed the ZERO button. Now the level just just shows 0. We are not able to drain the sump to get another ZERO on the device. Can anyone offer some suggestions on how to factory reset the device ? Ive head the manual and cant seem to find anything.

Please try with, prolink III basic, it´s free:
https://tools.emerson.com/OA_HTML/x...MMI=0001&section=10144&SP||EMR_PGOPTNS_IBE=01

I dont have a Hart communicator for my computer to use that software. However, Im bookmarking that software for future use.

I was hoping there was someway of doing it using only the ZERO and SPAN buttons.

Typically,
- the lower range value (LRV), the 4.0mA point is set when the zero button is pushed.
- the upper range value (URV), the 20.0mA point is set when the span button is pushed.

If the zero button was pushed at some elevated level, then that elevated level becomes 4.0mA and the span is reduced (considerably). The level is now zero and that's what the transmitter is reporting, because you shifted the zero to the current level.

I don't recall if the URV span changes when the LRV is reset, but, at a minimum, you need to re-zero the transmitter when the level is at its low point.

You might have to re-span it (URV) but you can tell once it's been re-zeroed whether the level values are correct or not.

danw said:

Typically,
- the lower range value (LRV), the 4.0mA point is set when the zero button is pushed.
- the upper range value (URV), the 20.0mA point is set when the span button is pushed.

If the zero button was pushed at some elevated level, then that elevated level becomes 4.0mA and the span is reduced (considerably). The level is now zero and that's what the transmitter is reporting, because you shifted the zero to the current level.

I don't recall if the URV span changes when the LRV is reset, but, at a minimum, you need to re-zero the transmitter when the level is at its low point.

You might have to re-span it (URV) but you can tell once it's been re-zeroed whether the level values are correct or not.

Click to expand...

Yes, that is how it works.

I was really hoping to avoid getting the sump down to a low point to reset the zero. The transmitter is mounted pretty low on the sump and getting the level down will required a few hours of down time.

The alternative is setting it up with HART, but that requires either
- a HART modem and software
- a HART communicator

Some smart transmitters (Siemens DSIII) can be configured with the local display and the pushbuttons, where you 'enter' the LRV value.

You'd have to check the 3051 Rosemount manual to see whether that's the case with the 3051.

I wish we had access to a HART communicator. Even the software and cables are expensive.

The newer models of the Rosemont have a LCD display that you can control with the Zero and Span buttons. However, this model doesnt have a screen. Just the 2 buttons.

HoldenC said:

I wish we had access to a HART communicator. Even the software and cables are expensive.

The newer models of the Rosemont have a LCD display that you can control with the Zero and Span buttons. However, this model doesnt have a screen. Just the 2 buttons.

Click to expand...

I think the 3051 has a LCD as an option.

You don't have any shut off valve towards your process? So you could disconnect it from the process and then zero?

On a lot of DP level apps, the 'zero' level is not at the transmitter's elevation, it's above the transmitter elevation, which means that 'zero' is adjusting for some liquid level above the elevation of the transmitter and disregarding that level, considering it 'below zero'.

Removing the transmitter and zeroing it in air would not account for whatever liquid level is above the transmitter's elevation but considered below 'zero'.

danw said:

On a lot of DP level apps, the 'zero' level is not at the transmitter's elevation, it's above the transmitter elevation, which means that 'zero' is adjusting for some liquid level above the elevation of the transmitter and disregarding that level, considering it 'below zero'.

Removing the transmitter and zeroing it in air would not account for whatever liquid level is above the transmitter's elevation but considered below 'zero'.

Click to expand...

That's true. We need to see how it's connected to process, how it looks like to determine what is what. And also as you noted, what process level 0 is.

If you can remove it and don't have the proper calibration equipment, you can easily make yourself a U-pipe to calibrate the zero, if zero isn't equal pressure on both sides of transmitter. It just takes some see through hose and a some connectors and water.

Our set up is just the single sensor on the sump. I do know what you are taking about with the 2 sensors though.

We dont have a shut off valve, but i didnt think about adding one this morning. Also adding a drain plug to it. That way I could shut off the valve and drain any pressure.

I have a Hart modem for my laptop but before I went that way I occasionally rented a Hart 475 communicator. If you can find someone with one for rent that would be the cheap and quick solution.
A cheap but not quick solution is what I did after a few rentals. I bought a maktek used modem (serial) off ebay and found some software online.

HoldenC said:

Our set up is just the single sensor on the sump. I do know what you are taking about with the 2 sensors though.
.

Click to expand...

Which post talked about 2 sensors?

Can you provide the complete catalog number of your transmitter?

Mickey said:

Which post talked about 2 sensors?

Can you provide the complete catalog number of your transmitter?

Click to expand...

Sorry about the 2 sensor thing. I was reading and posting while really busy and I got confused on some things.


The level transmitter is just mounted on the side of a sump. The readings aren't super important, just as long as I know my limits. For instance, the way the level transmitter read before the mix up was 100 was right at overflow, and 30 was right about where the sump would try to suck dry. The suction line from the sump is about 2ft from the bottom of the sump. This gives space for anything metal that may fall in the sump a place to settle and not be sucked into the pump.

The only info I have is what is posted above, and also this P/N: 03031-0001-0002

This morning, I was able to lower the sump level to the lowest point i could without sucking dry, and I zeroed the device. The device is still showing zero right now. Hopefully, I can refill the sump later today and push the span button and hopefully get things working right.

DwSoFt said:

I bought a maktek used modem (serial) off ebay and found some software online.

Click to expand...

1. Pactware is free software but requires a device specific (Rosemount 3051) DTM file to do anything other than 7 or 8 'Common' HART commands.

2. At one time, Mactek warned serial modem users that the use of USB/RS-232 converters could result in interrupted communications. I never got them to elaborate, but it's worth knowing. There was a serial setting that needed to be turned off (buffering?) but I can't find that note at moment.