Host Engineering Forum

General Category => General Discussion => Topic started by: maciek on March 24, 2022, 08:30:50 PM

Title: isolated analog signal
Post by: maciek on March 24, 2022, 08:30:50 PM
is the analog signal coming out of the brx plc or the analog madules that you guys have isolated? some of the cheaper dc drives that i like to use require an isolated analog signal.
ideas welcome.
Title: Re: isolated analog signal
Post by: ADC Product Engineer on March 25, 2022, 07:18:07 AM
What you need is a signal conditioner.
Title: Re: isolated analog signal
Post by: Controls Guy on March 25, 2022, 01:08:38 PM
The onboard BRX analog is floating.    I recently had an app that will field with a variety of unknown existing VFDs, and I was concerned that some might need a floating analog, so I asked BobO and he said they were.

Although, if you have multiple drives connected to the same module, isolators is a better idea.
Title: Re: isolated analog signal
Post by: maciek on April 02, 2022, 11:21:20 PM
what does floating analog mean?
Title: Re: isolated analog signal
Post by: Controls Guy on April 02, 2022, 11:31:14 PM
It's a differential signal without a fixed reference to ground.  If you wire it to a receiver that is referenced to ground, and the voltage is non-zero, the signal will "float" to meet it and nothing will burn up. Same type of signal you'd get from a signal isolator or signal conditioner.
Title: Re: isolated analog signal
Post by: BobO on April 03, 2022, 12:50:38 PM
Not related to the question, but we are prototyping a redesign of Host analog that will eliminate the FPGA. Think it has a fairly decent chance of working, and if so, we'll fast track production.
Title: Re: isolated analog signal
Post by: Controls Guy on April 03, 2022, 05:45:15 PM
Excellent news!   Thanks for working on that!  Fingers crossed.

Similar specs to the current Host product?
Title: Re: isolated analog signal
Post by: BobO on April 03, 2022, 11:57:35 PM
Excellent news!   Thanks for working on that!  Fingers crossed.

Similar specs to the current Host product?

Ideally identical. Analog section the same. Processor and backplane redone, but should be comparable.
Title: Re: isolated analog signal
Post by: maciek on April 05, 2022, 07:24:06 PM
so to be sure and excuse my ignorance, what you are saying is that i can  take the brx plc onboard analog out signal and wire it directly to one of my kb drives
that require an isolated analog signal and i will not blow anything up? BOB O