PB110a Booster Grounding

The PB110a is pictured on the left.

Problem: Locomotives stall between boosters crossing even though I installed a Booster Common.

Why: Some PB110a were shipped from the factory with the Booster Ground (Booster Common) screw installed in the disconnect position. A screw installed in "ground disconnect" position prevents the chassis as acting as a Booster Common connection even if you have the booster common wire attached to the bottom case screws.

Solution: Verify the PB110a internal "ground" screw is in the correct position as shown below.

What are conditions that required a functioning booster common?

There are two independent reasons to have a booster common:

1) You have more than one booster on the layout. If you only have one booster, simplistically just called the command station since it is often integrated inside, STOP. You do not need a booster common.

2) You have an engine with "offset wheel pickup" will stall/Stop when the engine crosses over a Booster Power District involving this booster. Typically a older model of a steam engine will get it's electrical pickup from one rail on the tender and the other rail on the engine itself. In other words, the none of the wheels pick up both sides of the track power. Old Tyco diesel engines had offset wheel pickup too. That allowed for rubber traction tires! A properly functioning booster common solves this problem.

What is a Booster Power District (Booster District)?

Booster Power Districts can only exist if there is more than one booster used to power the layout.

Booster Power Districts can consist of one or more Power Districts (create by the use of DCC Circuit Breaker of some kind) that are all feed by the same booster. In other words, the booster output is shared with by multiple Power Districts.

Even if there are no DCC circuit breakers involved, a Booster Power District is installed like a any power district with insulated rail joiners (rail gaps) in the track to isolate one district from another.

To learn more about Power Districts, go here: Boosters & DCC Circuit Breakers

How do I find out if the Booster Ground connection is correct or not on the PB110a?

Even if you connected the booster common wire to one of the 4 screws on the bottom of the case, the PB110 internally may not be setup to support it.

You must inspect inside the booster and check in the center back of the booster. Look at the drawing to the left. Note the words locating the "Silver Ground Pad". In that location there are also two screws locations side by side.

A properly grounded booster will have a screw installed in the hole on the right side. If there is no screw, move the screw over from the left hole (Disconnect Position) to the right hole (Connect Position).

It is OK to have one screw missing on the left side since that allows one to change the connection back to it original position. Think of the screw as a switch. It toggle between the two screw holes. The left screw location location is only needed for a wiring system called "common rail".

3/25/17