**RESOLVED** MPU11 and DC3IOB doubts

[juandres]

Good morning engineers.

i have many doubts , i hope you would help me please???

MPU11 and DC3IOB power supples would connect to 220 VAC directly?

Is The EMI filter so necesary?

Is The Jog pendant really necessary?

if the machine have three SEM servomotors, (MT30R4-58) , 145 volts and 32 amp-pulse each one, the DC3IOB and "Capacitor & Bridge Combo" can support that?

Thanks a lot for your answers.

[bezelchuck]

Hi
I'm just installing my outfit at the minute and am running both my mpu11 and gpIO4D power supplies on 240v ac single phase at present as this is easiest for me while testing, they'll be connected to the machines 115v ac supply eventually but I'm still picking out certain bits of that circuit at present.The Ajax website has an FAQ section for the mpu11 based kits which answers that question here :
http://www.ajaxcnc.com/mach_cnc_systems_faq.htm

I'm not intending to use the jog pendant, instead I am just having feed and speed overrides and cycle start and hold buttons that will be wired in as inputs and configured in the plc, I prefer this as it will match my other machines.It involves a bit more work though to install like this obviously.I posted the question on this forum about it and was told its perfectly possible.

Best of luck
Phil

[cncsnw]

The logic power supply for the MPU11 will run on anything from 85VAC to 264VAC.

The micro-ATX supply for the DC3IO probably has a 110/220 voltage selector slide switch to allow it to run on 220V if desired.

The EMI filter in the 24VAC output of the control power transformer is, I believe, an anachronism left over from some earlier generations of Centroid PLC hardware, where the logic power for the PLC unit was derived from the 24VAC source. If that is true, then you don't need it.

It is possible that Centroid has retained the EMI filter in order to filter out spikes generated by the contactor coils, to keep them from getting back to the supply lines and interfering with other devices. However, as long as you have appropriate suppressors (e.g. Quencharcs or varistors) on each contactor or solenoid coil, then you shouldn't need additional filtering.

The jog pendant is not absolutely necessary, but it is sure handy.

The MT30R4-58 motors should run fine with the DC3IOB. I would probably go with the higher-current (15A) version, unless this is a Series 1 size machine for which those motors are overkill at their rated torque.

145VDC would be higher than the recommended bus voltage for the DC3IOB. Are you planning to use one of Centroid's transformers, or use one from the original control? If you are using Centroid's transformer you will end up with around 120VDC. The motors will run fine on that.

If you are using an existing transformer, see if you can find out what its secondary voltage is. If it is around 90VAC or less, you will be fine. If it is over 100VAC, you should look at getting one of Centroid's transformers. In between, toss a coin.