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Vision Microsystems

ExtraKatana

Well Known Member
Does the older system from the 90's allow the new V100C (I think that's it) to be plug and play? you can use the existing probes? Plug and play would be nice.
 
There were 3 versions of systems sold by VM, see pic below.

Screen Shot 2021-01-12 at 3.16.06 PM.png

There was a lot of commonality between the EPI800 and VM1000 transducers and probes. Both systems were for sale by VM at the same time.

I have compared the wiring information in my EPI800 manual with the VM1000C manual and it is not obvious that the transducers are compatible. It does look like the EGT/CHT probes would be compatible, but I have no way of being sure.

If you have a VM system and certain functions are acting intermittent or flakey, the first place to start would be to change out the clock chip.

Do you know when yours was last changed?

I've done my clock chip 3 times in 24 years of ownership. This past summer the fuel pressure started acting up (going high at cruise). I put a new clock chip in (it was due, they only last so long) and now the fuel pressure is functioning properly.

I found this in one of the articles written by Reggie back in 2012 (linked in a post further down thread) "The 4th generation represented the final iteration of the venerable EPI-800 and VM1000 product line ... the next product, the VM1000C was essentially a clean slate design eventually acquired and improved by JP Instruments." So I would be skeptical of backward compatibility.
 
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I put a new clock chip

Interesting stuff Dave. Any source and maybe step by step procedure somewhere?
My ship sports a VM1000 and all indices good, but for the FF, which is working but flashes continuously...
 
VM1000s in certified aircraft often have an 8 year life on the DPU memory pack.

Vision Microsystems Doc No 5013900 describes how to change the chip.
 
Reggie wrote some excellent articles back in 2012 about the Vision Microsystems EPI800 and VMS1000. The article "Vision Microsystems VM1000 & EPI800: Brains, Batteries, & Busses" explains the real time clock chip (see link below).

This past August I purchased a new chip from Mouser for $15.11 plus shipping.

To change the chip you will need to remove the wiring and ribbon cable from the DPU, remove the cover from the DPU, find the chip on the top circuit board and replace it. On my plane I take the DPU out and do the chip change on the bench.

Here are links to the articles written by Reggie.

Vision Microsystems VM1000 & EPI800 Displays -- How the Backlights Work & Fail.

https://vansairforce.net/community/showthread.php?p=622685

Vision Microsystems VM1000 & EPI-800: How to Avoid the "MPT Blues"

https://vansairforce.net/community/showthread.php?t=82715

Vision Microsystems VM1000 & EPI800: Brains, Batteries, & Busses

https://vansairforce.net/community/showthread.php?t=84322

Vision Microsystems VM1000 & EPI800: What version do I have?

https://vansairforce.net/community/showthread.php?t=86808

Vision Microsystems EPI-800 & VM1000 Displays: LCD Precautions & Black Ooze Failures

https://vansairforce.net/community/showthread.php?p=794570

Also, back in 2014, John P, discovered that on his VMS1000, he needed to replace the digital processing chips and that solved his problems. Here is a link to that thread:

https://vansairforce.net/community/showthread.php?t=115116

I swapped PM's with John P this fall and his unit is still operating properly. Also, I check with Mouser and the digital processing chips referenced by John P are still available.

Unfortunately, on my older EPI800 the digital processing chips are Texas Instrument and discontinued. I could not find an alternative supply.

Hope this helps.
 
Thanks a bunch guys!

Super Dave, sure will help :)
I was on Reggie's site but didn't find too much of the info I was looking for. Now you're talking! Will bookmark and go thru these threads.
My unit is labeled 2002 on the upper display, and as stated above all is good but the FF.
Probably time to replace that chip :cool:
 
Just installed a new battery in mine using the following procedure. Made everything work like new.

Removing and replacing battery and re-programming the VM-1000

Purchase part no. M48T02-150PCI from Mouser (about $25 with shipping)

Remove data box from aircraft and then remove only the back panel. Find the Timer then just pull it off the circuit board. I used a pair of pliers because it was on their pretty good. Mark the old one with a pen so it doesn’t get put back on. Push on the Timer. It goes on very snugly. Reinstall the data box.

Replacing battery will zero out the engine time. (don't forget to write down your current time before removing the battery) To re-load engine hours, follow the steps below:

Programming the VM-1000

Carrying over your airframe or engine hours.

STEP 1- Accessing Set Mode -With power off, press and hold buttons 1, 3, 5 and then turn on power. Wait until the displays start reading out values and then release buttons.

STEP 2-Selecting decade to change- Press button 4 once to move to the next higher decade on the digital engine hours display. There is no visual indication for this change other than when you change the decade value (STEP 3). Pressing the button moves the selection to the left until it gets to the highest decade, after which the next press returns you to the lowest decade.

STEP 3- Changing the decade value- Press button 5 to increase the decade value as desired. If you go over 9 it will carry to the next decade.

To erase the entire engine hour’s value-Select the highest decade and increase it until the display clears. Do this TWICE, and then proceed per steps 1 thru 3.

When you are satisfied with what you see, shut off the VM1000.

Setting up your fuel tank quantity.

STEP 1: With power OFF, press and hold BUTTON 4, then turn power ON to the VM1000. Wait for the display test patterns to go off, then for the 'HRS', 'REM', 'BRN', 'ADD' indicators to activate, indicating that fuel tank setup mode has been activated.

STEP 2: You will program the tank size in whole units. Press BUTTON 3 for tens and BUTTON 5 for ones. If you accidentally went too high just repeat pressing BUTTON 3 until the display resets back to zero allowing you to start over.

STEP 3: If you like the value displayed, then press 'BUTTON 4' to accept the new maximum tank size, otherwise just leave everything alone and after 20 seconds the setup mode will automatically be canceled, leaving your previous tank size unchanged.

STEP 4: ADD fuel to your computer's memory according to “Adding Fuel to the Computer”.
 
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