Hello Experters,
   I try to control the water coolant by mach3. I buy the water pump (0.5 hp) at 220 volts.
  If I plug 220 volts,the water pump will run immediately.
 I know M-code,M07 is turn on and M09 is turn off for the coolant.
 Who can advise me for  the simple circuit to control the coolant?

 Mongkol

You will need to connect a relay with a 5v coil to Mach and the contacts of that relay will control the 220v to the pump. How you connect things will depend on the hardware you have connected to the parallel port, if using a breakout board it may already have a relay on it that you can use.
Hood

Mongkol,

I have found that SSR's similar to this one are cheap and easy to use.

Tweakie.

Tweakie,

Where to buy? A link perhaps, or some other info?

Thanks!!

Something like this should work too.

On the Ebay page, they're some info about Mach3 setup too


http://cgi.ebay.com/2-Channel-Relay-Board-CNC-Mach3-PARALLEL-PORT-12V-/110607796936?pt=LH_DefaultDomain_0&hash=item19c0bd0ac8

http://cgi.ebay.com/Four-4-Relay-Module-Board-8051-PIC-Project-12V-/400173556858?pt=LH_DefaultDomain_0&hash=item5d2c33e47a

http://cgi.ebay.com/Four-4-Relay-Board-AVR-PIC-Arduino-DSP-8051-5V-/110600393872?pt=LH_DefaultDomain_0&hash=item19c04c1490

http://cgi.ebay.com/5V-Relay-Board-Microcontroller-AVR-PIC-ARM-8051-/110523680066?pt=LH_DefaultDomain_0&hash=item19bbb98542


Jeff

Thosj,

http://shop.ebay.co.uk/i.html?_nkw=solid+state+relay&_sacat=0&_dmpt=UK_BOI_Industrial_Automation_Control_ET&_odkw=&_osacat=42899&_trksid=p3286.c0.m270.l1313

Without going into too much detail, SSR's switch the load at the zero crossing point of the mains ac waveform and this eliminates the voltage spike often associated with mechanical relays. Less noise = happier machine.

Tweakie.

Yup, I know about SSR's. I was interested in your "cheap" comment! US places like DigiKey have them but they're pricey. DC more pricey than AC. I found some AC SSRs at, http://www.futurlec.com/ a Chinese company, but shipping is cheap to US, and they seem to ship FedEx Next Day (!) for their cheep prices by default. I got a couple DC SSRs from them last year, they were out of 20 AMP so they sent 40 AMP for the same price, and they got to the US from China overnight for like $5!! It was interesting to track them from China, thru Alaska, to my door in one day.

I THINK SSR's fail closed, something to keep in mind when using them. I'm not the expert on this, but others have warned me of this condition.

Thanks for the link. I'll also check eBay US. I always forget that!

 All,
 Thank for the information.
Tweakie,
 I am little puzzled. It's ok for SSR's. Could you pls advise me of the simple circuit  onto SSR's. How to connect onto BOB?

 Mongkol
 

This may be of interest to some of you:

http://www.cartertools.com/tbbrb.html

Hope that helps-
Dave

I use this circuit with a slight modification to drive a relay, only one half of the pictured circuit is used. It's the third post.

http://www.denfordata.com/bb/viewtopic.php?f=4&t=1763&hilit=triac+mach

Instead of using the transistor to switch the logic signal you can use it to drive (or sink really) a relay. By connecting the relay coil (negative 0v) to the collector of the transistor and the other side of the relay coil to VCC (positive) you can use the transitor to switch the relay with a logic level signal. You'll need to add a diode to protect the circuit from the back emf of the relay, which goes accross the relay coil in reverse polarity.
You can build this circuit for less than a pound if you shop around, and if you're in the trade you'll get it down to 50p, and that includes the relay.