ETC L86 Service Note

ETC® Service Note

Power Cube Replacement in L86 Dimmer Modules

Overview:

L86 dimmer cards have one or two power cubes within their tray. The power cube is responsible
for chopping the wave so that we are able to dim conventional sources. This is done by allowing
the power cube to receive a low voltage control signal that turns the solid state relay on and off at
the proper times to achieve our dimming goals.

Reasons for failure come from short circuits in the cable or fixture. Due to V = IR V is a constant,
as resistance approaches 0, our current approaches infinity , which in this case will trip the breaker
or burn out the power cube.

Symptoms of a burnt out power cube may include a dimmer being stuck on or off.
Through the years ETC has had many revisions on parts and pieces that are used in the L86

dimmer card. Because of this we recommend that you see additional information before
proceeding, to see if this manual applies to you.

Note: If your power cube has screw terminals instead of crimp connections, please contact

ETC for assistance on choosing the appropriate power cube.

Tools Needed:

Phillips #2 Screwdriver
Pliers
Rubber gloves
Thermal Joint compound
Rubbing alcohol
Towels or rags
5/8” Nut driver with ground down tip (see additional information)*
3/8” Nut driver with ground down tip (see additional information)*

Note: See additional Information for tools marked with a *

Procedure:

Step 1: With your pliers, pull off circled wire crimps from relay.

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London, UK
Rome, IT 
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Service:
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Technical Services

Power Cube Replacement in L86 Dimmer Modules Page 1 Electronic Theatre Controls, Inc.

 Unit 26-28, Victoria Industrial Estate, Victoria Road, London W3 6UU, UK  Tel [phone]  Fax [phone]

Via Ennio Quirino Visconti, 11, 00193 Rome, Italy  Tel [phone]  Fax [phone]

(Americas) [e-mail] 

www.etcconnect.com 

 3031 Pleasant View Road, P.O. Box 620979, Middleton, Wisconsin 53562-0979 USA  Tel [phone]  Fax [phone]

 Ohmstrasse 3, 83607 Holzkirchen, Germany  Tel [phone]  Fax [phone]

QSF 4.1.9.1



 Rev A  Released 2009-07

Copyright © 2009 ETC. All Rights Reserved.  Product information and specifications subject to change.

(UK) [e-mail]  (DE) techserv-hoki@e tcetcco nnect.com .com 

(Asia) [e-mail]

ETC Service Note:

Power Cube Replacement in L86 Dimmer Modules

Step 2: Next remove control from relay.

Note the connector on
this card has 6 possible
connections but only
the center 4 are used.

Step 3: Remove 2 circled screws. Keep in mind that differe nt models might have nuts on

them. This will require you to use specially modified tools. See additional
information for more details.

Step 4: With a towel or rag, remove the joint compound. Apply rubbing alcohol as needed to

remove excess residue left behind.

Power Cube Replacement in L86 Dimmer Modul es Page 2 Electronic Theatre Controls, Inc.

If you are using chemicals to
remove old joint compound, we
recommend wearing gloves.