adccommunitymod (AutomationDirect) asked a question.
Created Date: October 12,2010
Created By: DetroitSound
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Today I had a failure of an Allen-Bradley 160-BA03NPS1 AC drive. I was able to borrow one from another machine, we are back in production and the day has been saved. But eventually we will need the other machine. The application seems rather simple - it is being used as a drive providing four fixed speeds. It is operating a 1 HP blower which does not operate under brutal conditions, it is for an ultraviolet curing unit. Specs for the A-B Bulletin 160 drives show that it is a sensorless vector type. However, load on the motor is essentially constant. I would prefer to find one that will physically fit into the same space as the original. It is just slightly larger than a 1hp GS1 drive and smaller than a GS2 drive. It is also 480 volt. Does anyone see a problem with using a V/F drive as opposed to a sensorless vector control for an application like this? It seems like if the operating conditions are essentially constant a simple V/F drive should do nicely. Any advice is welcomed.
Created Date: October 12,2010
Created by: Adisharr
I don't think you'd have any problem using a simple V/Hz drive in that application. From my limited experience with that mode, they usually don't work all that great on small motors anyway due to the small amount of current. They might have gotten better over the past few years since I 've used one.
Created Date: October 13,2010
Created by: milldrone
DetroitSound,
The biggest contribution a sensorless vector drive brings to the table, is to control the motor irregardless of motor slip. So If you need to control a 1750 rpm motor when it's below 50 rpm you need sensorless vector. I'm guessing that your app does not need this low speed, so you should be fine.
Created Date: October 13,2010
Created by: DetroitSound
I believe it is a 3450 rpm motor and at its lowest speed it's running at 23hz, or about 1/3 speed. I do not believe slip is a factor.
The blower is important, in that the lamp operates at approx. 1500f and it will cause all kinds of mayhem if there is no cooling air (meltdown, fire, etc)...but if it overcools it drastically reduces the power output and it won't cure properly, so although there is some leeway with the motor speed it needs to operate at a constant speed depending on which speed the equipment selects. I can adjust the drive to the speed needed for each stage by checking temperature, but once that is set there is no adjustment needed.
Created Date: October 18,2010
Created by: DetroitSound
Further questions on the GS2
I have a GS2-41P0 ordered. The main difference is in the speed control wiring - the original unit had five programmable fixed speeds (only four were used), in such a manner that when the run contacts were closed but none of the speed contacts, it would run at its lowest speed - low enough not to seriously affect warmup, but fast enough to prevent burning the stock on standby. The selected "low " speed would come on when the shutter opens, speed 2 with the shutter open and the lamp on medium, and speed 3 with the shutter open and the lamp on high (with the shutter closed it is at the lowest speed regardless).
I can avoid rewiring the existing speed 1, 2, 3 relays in the machine if I program 5.01, 5.02 and 5.04 respectively for the desired speeds. But I don't understand how to make it run at a specific speed as soon as the run/forward contact is closed. Or would I have to achieve that through bit addressing? If it was something that I knew nobody would touch I could use the internal speed pot on the GS2 but some of the people (like my boss) have a tendency to monkey with things they don't understand and a knob is just begging to be turned, possibly with serious consequences.
Created Date: October 18,2010
Created by: milldrone
I can avoid rewiring the existing speed 1, 2, 3 relays in the machine if I program 5.01, 5.02 and 5.04 respectively for the desired speeds. But I don't understand how to make it run at a specific speed as soon as the run/forward contact is closed.
DetroitSound,
Set parameter 4.00 to 2 and install fixed resistors that meet your speed requirements on the 0-10V input.
Created Date: October 18,2010
Created by: DetroitSound
I also found out another thing HORRORS!!:eek:
The original drive was 1hp, I did not go to look at the motor (get out a ladder and climb a rack)...this morning I went to look to get nameplate info and I found that it is a 3/4 hp motor. Do you see any problems using a 1 hp drive on a 3/4 hp motor?
Created Date: October 18,2010
Created by: milldrone
Do you see any problems using a 1 hp drive on a 3/4 hp motor?
It's not an issue. just set the P0.01 parameter according to motor name plate.
Created Date: October 20,2010
Created by: Rich19551
I can avoid rewiring the existing speed 1, 2, 3 relays in the machine if I program 5.01, 5.02 and 5.04 respectively for the desired speeds. But I don't understand how to make it run at a specific speed as soon as the run/forward contact is closed. Or would I have to achieve that through bit addressing? If it was something that I knew nobody would touch I could use the internal speed pot on the GS2 but some of the people (like my boss) have a tendency to monkey with things they don't understand and a knob is just begging to be turned, possibly with serious consequences.
I think I remember
P3.00 set 2
P3.01 Set 0 = Jog P5.00 set speed Close D11 to DCM
P3.02 Set 3 = Speed 1 P5.01 Set speed Close D11,D13 to DCM
P3.03 Set 4 = Speed 2 P5.02 Set Speed Close D11,D14 to DCM
P3.04 Set 5 = Speed 3 P5.03 Set speed Close D11,D15 to DCM
P7.0 Set 0 No PID
I think that right
Rich
Created Date: October 21,2010
Created by: milldrone
Rich,
The reason I did not suggest using the jog speed is because the drive needs to be in a stopped condition before jog will engage. If I'm understanding his requirements correctly he needs the fan to run constantly and cannot afford for it to stop.
He also did not specify, but I believe he is also trying to interface with some hardwired relay logic and this would require an extra input.
Please correct me if I'm wrong
Created Date: October 22,2010
Created by: Rich19551
Let me rephrase this. The GS2 drive needs a forward command (Di1 to DCM), if closed it will run at a preset speed (set min speed, like a jog). If closed all the time it will stay running at that speed (hard wired). Then closing Di4 to 6 or a combination of them you can come up with 7 different more speeds.
Di1 Forward/Stop
Di2 Rev/Stop
Di3 External Fault
Di4 Bit 1
Di5 Bit 2
Di6 Bit 3
Chapter 4-25 for bits settings
The manual has some typo that you have to read thru.
Rich
One thing I have to add, If GS2 is powered down the foward command has to be broken then reset, forgot that.