Control High Current Loads with MTH, TIU, and AIU

Table of Contents

1. Introduction
2. Basic Accessory Control
3. Controlling High Current Loads
4. Using MTH, TIU, and AIU
5. Setting Up the System
6. Adding 10 Amp Relays
7. Grounding and Power Supply
8. Using Relays to Control Track Power
9. Electrical Panel Connection
10. Programming the DCS Remote
11. Conclusion

Controlling High Current Loads with MTH, TIU, and AIU

If You're looking to control more than just basic accessories, such as items that draw a much higher current load including track power or a bank of accessories sections whole sections of your layout, even the room lighting, then you'll want to consider using MTH, TIU, and AIU. In this article, we'll go over how to set up this system and control high current loads with ease.

Basic Accessory Control

Before we dive into controlling high current loads, let's first go over basic accessory control. This is the most common use for MTH, TIU, and AIU. You can control switches and accessories off a single TIU, as many as 10 accessories in this case, off of the AIU. This is perfect for controlling items that are below the 3 amp limit.

Using MTH, TIU, and AIU

For this setup, we're using a single TIU, but the only thing connected to it is an MTH 21 volt power supply. This is constant power to the auxiliary power input. We do not have any other transformer connected or any Type of track power to it. This is only to control the TIU, all through the control cable to a single AIU. Now you can daisy chain up to as many as five AIUs off of a single TIU, so you have a lot of expansive capabilities.

Setting Up the System

To set up the system, you'll need to add 10 amp relays. You can buy these in two packs, four packs, up to eight and then just pair those up how you need to. They do need a power supply. In this case, we're using a 5 volt DC power supply. The relays are grounded here, going to the in and then out number one which triggers the relays on this eight bank.

Adding 10 Amp Relays

If you have items or a bank of items accessories, track power you want to control that are above the 3 amp limit, this is an option that you can add 10 amp relays. We have a bank of eight. You could add two more to this power supply, and you'd have plenty of power.

Grounding and Power Supply

In the background, we have a grounding bar and a power connector that we took out of a router. The power supply or excuse me the relays came from eBay, and then we got the other pieces through Jamco. We basically took one six conductor Arduino connector, split cut that in two, and then divide it and then move the wires accordingly around to suit our needs. Power supplied here on the red line, the wire comes in off the 5 volt DC power supply, and the ground is on the outside, the far right side which connects off of the power supply here then grounded.

Using Relays to Control Track Power

We've been using the relays to control track power. We love to do that. We've been using Lionel 180 watt power bricks through these relays to control track power. That's a perfect match, 180 watts 10 amps at 18 volts, and it works very well. You could do this with either side of a Z4000, old ZWS that type of thing. We would recommend late model power supplies with circuit breakers though. However, if not, if you run the old ZWS is to put circuit breakers in line. Some prefer fuses, but circuit breakers are a little faster to get to if they pop, and they work very well.

Electrical Panel Connection

Let's assume we have an electrical panel connection coming here which right now we just have an extension cord and basically showing 120 volts 20 amp circuit fed in here to the relay. We could put a circuit breaker in here. We would recommend a 10 amp, and we could have one here also on this side, one to protect the relays on either side here. We're using 14 gauge wire for this, and we just have a single outlet that we put together. We have a fan plugged into it again just using it for demonstration purposes only, and the light is currently right now turned on.

Programming the DCS Remote

To program the DCS remote, we go to menu scroll to system, scroll to accessory setup click on add accessory, run TIU1 AIU1, and let's say we want to program accessory Channel 3. We select that we scroll through here and give it a name. When we're done, we go to the letter d for done. Now we go to accessories, which we should see our items in this case. We've already pre-programmed channel one and channel two called them track one and track two. Now we're set. We're already highlighted on the track one or channel one rather, and we can just hit the on button, and on goes our light or our accessory and back off again.

Conclusion

In conclusion, using MTH, TIU, and AIU is a great way to control high current loads. With the ability to daisy chain up to five AIUs off of a single TIU, you have a lot of expansive capabilities. Adding 10 amp relays is a great option for controlling items that are above the 3 amp limit. With the ability to program the DCS remote, you can easily control all of your accessories with ease.