Good Relay Board

Discussion of the physical aspects
Post Reply
User avatar
oakbarn
Posts: 846
Joined: Thu Jan 05, 2012 2:28 pm
Bot?: No
Location: Texas
Contact:

Good Relay Board

Post by oakbarn »

is this a good board to use to power valves.

http://www.ebay.com/itm/130806507081?_t ... EBIDX%3AIT
JonW
Site Admin
Posts: 1721
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Good Relay Board

Post by JonW »

Yes and no. It would work fine, but it is the 5V version which would require a separate 5V power supply to power the relays. If your valves are 12V, get a 12V relay board and share the PS.

Don't confuse the 5V relays with using a 5V "trigger" output from the BCS. The relay board can have 5V, 12V or 24V relays and still be triggered by the 5V BCS outputs. Also don't use the 5V PS from the BCS to power 5V relays.
User avatar
oakbarn
Posts: 846
Joined: Thu Jan 05, 2012 2:28 pm
Bot?: No
Location: Texas
Contact:

Re: Good Relay Board

Post by oakbarn »

I do get confused with relay boards as I have never used them. I have a 12 vdc to 5vdc Regulator (https://www.amazon.com/gp/product/B00J3 ... UTF8&psc=1) that I am going to use to power the Relays. The Trigger says it need 5v at 0.35MA. Is that low enough for the BCS.

I assume that I hook the Regulated 5v to the VCC and the GND. The Out would go to IN-1 to In -8 and the BCS GND to the second GND as well. My 12+ vdc would go to C1- C8 nad the + to the valve NO1 to NO8.
JonW
Site Admin
Posts: 1721
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Good Relay Board

Post by JonW »

Yes, your wiring summary is correct. If you don't need the 5V regulator to drive anything else, then just buy the 12V relay board.

Powering relays and triggering relays are very different. You can power a 12V relay from your 12V PS and trigger it with the BCS 5V output.
User avatar
oakbarn
Posts: 846
Joined: Thu Jan 05, 2012 2:28 pm
Bot?: No
Location: Texas
Contact:

Re: Good Relay Board

Post by oakbarn »

Unfortunately, I bought the Relay Board some time ago. I ordered the 12vdc to the 5vdc Regulator to "fix" my mistake not getting 12 volt one. I mistook the 5 v as the trigger :oops: ( which is also is) not knowing that is was also the Relay Operating voltage :roll: as well.
relayBoard3.jpg
relayBoard3.jpg (224.03 KiB) Viewed 4073 times
User avatar
oakbarn
Posts: 846
Joined: Thu Jan 05, 2012 2:28 pm
Bot?: No
Location: Texas
Contact:

Re: Good Relay Board

Post by oakbarn »

I have a 12 vdc board as it was just easier to wire. I have some CR-05 valves that will work where I use 2 relays and reverse the positive and negative of the Blue and Yellow wire.

When you connect the Yellow Positive (+) and the Blue Negative (-), the valve opens

When you connect the Yellow Negative (-)and the Blue Positive (+), the valve closes.

I wired:

NC1 as Jumped to NO2 with a Blue Jumper
C1 is 12 vdc+
NO1 is Yellow wire to Valve
NC2 is Yellow Jumped to NO1 with a Yellow Jumper
C2 is 12 vdc -
NO2 is Blue wire to Valve

Out 7 is control for both IN-1 and IN-2.
cr-05 wiring q.png
cr-05 wiring q.png (138.69 KiB) Viewed 3952 times
Basically when the two relays are energized, the Yellow is Positive and the Blue Negative, when un energized, the Yellow is Negative and the Blue Positive.

This seems to work but am I doing it wrong or is there a better method? I have 8 Channel relay but will not be using them all anyway so the one board will do.
JonW
Site Admin
Posts: 1721
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Good Relay Board

Post by JonW »

You're basically doing the work of a DPDT relay using two SPDT relays.

I don't know about better, but there is a different way.

NC1 - 12V+
C1 - Yellow
NO1 - 12V-

NC1 - 12V-
C1 - Blue
NO1 - 12V+

I personally like buying the 3 wire valves that use either a single wire for triggering (other two wires have constant V+ & V- fed to them) or the valves that have a single wire that is constant V- and the other two are V+ to command open or closed. Using valves like this makes it simpler to use a SPDT relay.
User avatar
oakbarn
Posts: 846
Joined: Thu Jan 05, 2012 2:28 pm
Bot?: No
Location: Texas
Contact:

Re: Good Relay Board

Post by oakbarn »

I was wanting the 3 wire valves but I got the CR-05 five wire by error on the Shipper's part. I was trying to get these to work and they do have the feedback :D where I can add some LEDs so I know where the valve really is. I have lights for all my Pumps and have found that it would be really nice to have that feedback. I have two 2 wire NC Valves on my water supply so I can fill vessels that stop with a Float Switch (DIN). Occasionally, one of them does not open for some reason. They both occasionally "go on strike" and refuse to work. I have checked the wiring and even rerun new wire but I am convinced it is the Chinese Valves that are the problem. It only happens occasionally and some Brew days I have no issues at all. At least with the feedback loop, I could see it was "not open" or "open". I have never used Relay Boards and it has been a learning curve for me.

I think that the Relay Board for DC is the way to go vs Individual SSRs .

Positive Reasons:
Costs: Less than half the cost of 8 Individual Relays.
Size: More compact and easier to mount than 8 Individual Relays
AC/DC: Can be either
Note: Because of the Amperage Rating, I am using these for DC Valves.

Negative Reasons:
Single Relay Fail: If you do not have a spare open relay on the board, you would have to replace the entire Board.
Amps: Not as robust as Individual Relays and not enough for many Brew Widgets

I was confused at first about the Voltage Requirements of a Relay Board and what it means.
for this board: http://www.ebay.com/itm/130806508025?_t ... EBIDX%3AIT

8 Channel 10Amp SPDT Power Relay Module Board, DC12V Version

This item has been assembled, and electrical test passed.
OMRON G5LA-14 Power Relays.
LED indicator for each relay channel.
BC517 Darlington transistor driving relay, Improve the reliability of action.
FR-4 Fiber glass PCB ( Double Layer ).
Size: L150mm x W72mm x H20mm.

Power Supply: 12V DC / 400mA (relay all ON).
Input control signal voltage:
0V - 0.5V Low state (relay not-action),
0.5V – 2.5V (unknown state).
2.5V - 20V High state (relay action).
Input control signal high state current:
2.5V: 0.1mA.
5V: 0.35mA.
12V: 1.1mA.
24V: 2.4mA.

Relay Spec:
Manufacturer: OMRON, Part Number: G5LA-14 12V DC.
Contact Rating: 277 VAC / 10 Amp or 30 VDC/10 Amp.

it seems there are three different Voltages and Amperage Requirements on the Relay Board.

1. Relay Board Working Voltage(Power Supply): Power Supply: 12V DC / 400mA (relay all ON).

2. Trigger or Control Voltage. Since we are using the BCS:
Input control signal high state current:
5V: 0.35mA
3. Load Voltage: Contact Rating: 277 VAC / 10 Amp or 30 VDC/10 Amp

The Boards come in Different Relay Board Working Voltages on ebay.
5v : http://www.ebay.com/itm/8-Channel-10Amp ... SwKrhVcVFF
12v : http://www.ebay.com/itm/130806508025?_t ... EBIDX%3AIT
24 v: http://www.ebay.com/itm/8-Channel-10Amp ... SwBahVcXDQ


Basically, these are all the same boards as far as the Trigger and Load are. The difference is in the Relay Board Working Voltage(Power Supply).

So if using for AC, any would do but if you have a Power Supply that is 24 vdc for Valves, then get the 24v model so you do not need another Power Supply.
If using for 24vdc valves, get a 24v model so that your Valve Power Supply can Supply the Relay Working Voltage as well.
If using for 12vdc valves, get a 12v model so that your Valve Power Supply can Supply the Relay Working Voltage as well.
If using the 5v Model, the 5+ of the BCS is NOT a Power Supply for the Board. You will need a 5 vdc Power Supply external to the BCS to power the Relay Board. The BCS can supply the Trigger.

Hopefully I have this correct.
Post Reply