The Yokogawa vortex flow meter Hart475 will not connect
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Reason analysis for the inability to connect a vortex flow meter Hart475? Today I encountered an issue with a Yokogawa vortex flowmeter model 475 – it wouldn’t connect, even after trying 250; the reason is unknown. The instantaneous flow rate of this flow meter is much lower. Firstly, 475 is intact; other flowmeters have been tried and can be connected. Please also analyze the reasons, gentlemen
It wasn’t made clear. First of all, is the HART475 you’re using domestic or imported? Domestic ones may not be able to communicate
Your vortex flowmeter does not comply with the HART protocol; it might use the Brown protocol, in which case a BT200 communicator is required
1. Your controller isn’t domestic, right? If it is Emerson’s 475, please see the next point. 2. Does your vortex flow meter support the Hart protocol? If it’s not from E+H, it usually has buttons; you can take a look there. If it is from that brand, please see the next point. 3. How did you add the 250Ω resistor? You should disconnect one wire and connect the resistor in series within the circuit, then place the probes of the handheld device at both ends of the resistor. If you follow the next point, 4: What is the voltage received by your controller? It can be seen in Hart’s main menu, 4,1: a voltage of at least 1V is required for communication. 5. What is the address of your flow meter? The default polling address is 0, but the meter’s address may change; you can try changing it to a value between 0 and 64. 6. Do you have any other flowmeters of the same model from the same batch? Can it be connected? If neither option works, it means the version is too low and the controller version needs to be upgraded.
Yokogawa’s might use the Brain protocol, so a controller that supports the Brain protocol is required.
The Brown protocol was originally proposed by Yokogawa; check whether your flow meter uses the Brown protocol or the HART protocol
Yokogawa meters come in two types of protocols: HART and Brown. Meters using the HART protocol communicate via 475, while those using the Brown protocol communicate via BT200. The meter’s label usually indicates the communication protocol used.
First, check the model number to see what type of communication protocol is used. Yokogawa’s smart instruments have their own BRAIN protocol; it’s not necessarily HART
Check whether the instrument supports the HART function; if not, use BT200
1. Emerson’s 475. 2. Supported, Yokogawa. 3. Yes. 4. 22.3V. 5. It has been tried. 6. Shanghai Yokogawa vortex flowmeters of the same manufacturer and type purchased in the same batch (with different pipe diameters) can be used. It was possible to install it two years ago, but not anymore. It’s a flow meter used for trade settlement; it has been unused all this time. The flow rate on the other side is 110 t/h, while ours is 20 t/h. The medium is steam condensate, with a temperature of 145°C and a pressure of 0.34 Mpa(G)
If HART is not supported, do I still need to post a request for help?