Home Forums General Discussion Technical Questions Tac20

Have a 1011 fault. Car is sitting below bottom floor, won't run on auto or cartop inspection. Mcc1 relay is flickering. Thats all the info i have

Fault Description:

The motor contactor failed to Energize (MCD/MCE)

MCD is Active, or MCE is Inactive After a Run

Possible Causes:

A defective MCD input

A defective MCE input

A defective MC contact

Defective relays

Possible Solutions:

Verify the starting current on the solid state starter

Found bad contact on cgcf relay that kept run input low on softstart. Blue finders strike again

Whats involved in replacing main cpu board in these. Are they readily available from vert. Express

They are very available from ve u will need ims from a friend

You only need ims or do you also need lon adapter

Somebody else might have more input. I believe if you have downloaded lon, you will not need the adapter. If it is a complete loss you will need it.

i believe solid is correct, if you have downloaded the lon config files, and car parameter/io files, you should be able to install the new cpu and upload saved files and be back in service, without ever having to use a lon adapter. hopefully the new cpu will come with the correct generic software. if not, then you would have to upload new software.
I have never had to just replace the cpu only in a running tac 20 with lon, so I'm not 100 percent sure that i am correct. I have built a tac 20 tester from scratch and added software,config files, then used lon adapter to program new ln boards. maybe i will try to just remove the cpu and put in a new one and see if the ln boards will still work with just the cpu replaced. any thyssen guys have the absolute answer? thanks

If it is a LON job a LON Adapter will be needed when a new CPU is installed. Done many and you will definitely need it to activate the LON Network.

thanks rolly,

I'm trying to get a lon adaptor to work with ims my company got from a company called echelon. I think I have the driver software installed to allow the adaptor to work but I think I may be doing something wrong because when I go into the lon manager section of ims and wink a node nothing happens. Does anyone have any experience with this.

NOTE: Before beginning, make sure that the LON drivers have been installed
NOTE: When the Advanced LON Manager opens the adapter, but does not communicate with any node.

1. CLOSE IMS if opened!

2. INSTALL LONWORKS

3. REBOOT

4. Open the Control Panel from the Start Menu.

5. Open LonWorks� Plug 'n Play (ONLY PLUG AND PLAY)from the Control Panel .
NOTE: If LonWorks Plug 'n Play is not an available option, the drivers for the LonTalk card will need to be installed.

6. From the LonWorks Plug 'n Play window, left-click the pull down arrow under NI Application .
NOTE: PCC10NVI is the program default setting, every time it is installed.

7. A list of options will appear under the NI Application box. Left-click NSIPCC

8. After NSIPCC appears in the NI Application box, left click APPLY in the LonWorks Plug 'n Play box.

9. Click the Diagnostics button (the Diagnostics window will open).

10. Click the Comm button, and then click the YES button.

11. Click the OK button, and then click the YES button.

12. Click Ok Button.

13. Open IMS, Open advanced lon manager

The adapter should now be operational.

I thought this was a MCE/ MCD fault? It's got nothing to do with LON. Replace all the finder relays on the boards, you have to replace the spring type relay holders too. (Very important)

I was replying to the post right before my post...... He asked about LON.

There are several bulletins and re-wires on this issue, the flickering relay rings a bell. The plug in suppressor on MUTS should be replaced with the wire in type. These MCD/MCE faults are also often caused by back contacts on the valve relays on the bottom of the 188E.

What's the consensus on the blue finder relays these days? I had a car go down due to the NC contact on VC1A causing the loss of the MCD input.

I have a stash of 24vdc finder relays with blue, clear, and yellow covers. Is one of these preferred over the other?

I think the blue ones are the only that are legal. They have to be force guided to meet code. The orangish ones are 120vac. Not sure on the clear ones but I think Otis was putting in the kind of neon yellowish ones that were not force guided.
I have personally seen lots of problems with the shrack relays in blue bases and do suggest using blue finders if you have them or replacing the board or bases if you’re inclined.

You have to have to correct socket for the relay you use or there is problems.

That's good that you mentioned force guided since now that I look, the relay that failed was not this style. I know the customer just had the previous company replace all the relays in the controller and now it looks like we'll need to get those out of there. I'm aware of the shrack relays, have a few but I've read too many of your posts to feel comfortable using those.

Looks like my clear and yellow cover spares I have are the same part number and are force guided.

https://imgur.com/a/X0K2dys

Ya Rolly seems like common sense right?
But at some point it was decided at Thyssen that the blue finder relays were unreliable and must be replaced with the Schrack relays. It happened before I came to service but a quick side by side comparison of the 2 relays should tell anyone that the Schracks will cause problems in the Finder bases.

I don’t see a problem with those other Finder relays you have. Strange that the one you have that isn’t force guided is a Blue one. Does it look like it’s been opened?