Paperless Recorder Supporting HART (multidrop)

The Google search is useless. The 4 letters in the word HART are also part of the word 'chart' and since paperless recorders have screens called 'charts', there will be hundreds of Google hits that have nothing to do with the HART communications protocol.

I follow the paperless recorder market and I know of no paperless recorder that retrieves HART data whether point-to-point or multidrop.

Any instrument that is HART compliant will support multidrop HART communications, but wired multidrop HART communications is a project in itself, requiring a HART multiplexer and the associated software/firmware to read the data, and in some cases licensing the HART server software. Paperless recorders are not PC's and it is my opinion that paperless recorders do not have the programmability to handle the output of a HART mux.

If I needed the precision of digital communications (meaning, without the uncertainties inherent A/D, D/A in analog 4-20mA signals and the limitations involved in totalizing with only an analog output) I would look at one of two approaches.

1) HART-to-Modbus converter(s) and use a paperless recorder that is a Modbus master/slave and can handle Modbus, like Honeywell Trendviews recorders. That's assuming that the coreolis meters can not be fitted with a Modbus card.

Moore Industries:
HCS HART® Concentrator System HART-to-MODBUS Converter
http://www.miinet.com/products/sg_hart.shtml

GiE, model HRT2MDB
http://hartmodbus.giemdp.com.ar/

www.renuelectronics.com. model is Gwy-800

2) The other approach is to use wireless HART with a wireless converter for each flow meter. The network accessible data from a wireless HART gateway is Modbus.

Either approach uses the Modbus protocol, which is available on paperless recorders, whereas HART is not.

This approach is probably more costly, given the cost of wireless HART gateway.

The caveat to either approach is that one would need to be very clear about exactly which data is to be retrieved and that the device used in either approach actually can fetch that data. It's my impression that at this release level, that the wireless HART converters are limited as to which HART data is accessible.