# Powerflex 700 - Preset Speeds



## glen1971 (Oct 10, 2012)

I'm working on a couple of 700's that replaced 2 speed starters, and I'm having some grief with using the preset speeds. They are wired using DI1 and DI2 for the 2 speeds (30 Hz and 60 Hz) and DI3 is used for a "run" command... Every time there is a power bump, the drives won't restart automatically. The run in put on DI3 comes from the Vibe Switch and a local on/off at the motor. The Inputs to DI1 and DI2 come from a PLC driven relay... They have DI1 (Par# 361) set to "15" and DI2 (Par#362) set to "16"... I tried looking at the table on Page 3-60 of the manual for the Speed Select info, but couldn't make heads or tails of it... I tried disabling DI3 (changing it to not used), but then the drives wouldn't run when DI1 or 2 were true...
I'm sure I'm missing something simple...


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## Hybwolf (Jul 31, 2011)

P093 speed reference B = "preset speed 1"
P101 preset speed 1 = 30 hz
P102 preset speed 2= 60 hz
P361 DI1= 15 speed select 1
P361 DI2= 16 speed select 2

Been a while since I set up speed selects. i think this should do it.


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## Tsmil (Jul 17, 2011)

It sounds to me that you may be sending the start signal to the drive before the drive is ready to accept it. By default, the drive must be ready before receiving the run command.

However, parameter 168 will allow this to be changed.


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## JRaef (Mar 23, 2009)

Yep. If you have left 168 at default, the Run command must be toggled if there is a fault, even if the fault was automatically reset. But change that at your risk.

What do you mean by "power bump"? A loss of power, or a glitch like a short dip? What you might be better off doing is filtering that a bit. For example if it is an under voltage fault from a dip, you might consider disabling the UV trip and make it an Alarm instead. The Nominal DC bus voltage on a 480V drive is 648VDC. The AC Input UV _trip _setpoint is 280VAC, which equates to about 396VDC on the bus side. The drive has a 2nd level of forced shutdown at 305VDC on the bus. So if you disable the UV trip function, you still have that final level below it to back you up.


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## glen1971 (Oct 10, 2012)

JRaef said:


> Yep. If you have left 168 at default, the Run command must be toggled if there is a fault, even if the fault was automatically reset. But change that at your risk.
> 
> What do you mean by "power bump"? A loss of power, or a glitch like a short dip? What you might be better off doing is filtering that a bit. For example if it is an under voltage fault from a dip, you might consider disabling the UV trip and make it an Alarm instead. The Nominal DC bus voltage on a 480V drive is 648VDC. The AC Input UV _trip _setpoint is 280VAC, which equates to about 396VDC on the bus side. The drive has a 2nd level of forced shutdown at 305VDC on the bus. So if you disable the UV trip function, you still have that final level below it to back you up.


Sorry about the confusion... I'll elaborate...
By power bump, I meant either one or more of the line fuses that feed the utility transformer to be open. This would start the emergency generator and transfer the MCC load to the Emergency bus. We spent a fair amount of time after the MCC was replaced to ensure that the transfer timing was long enough so that all the drives had totally powered down and the HMI's went blank. We found that sometimes a drive would get "hung up" and not know what to do if the power was restored before the drive's DC bus went to 0, and the HMI's went blank..
Parameters that I've changed on them all, beyond the motor data, typically are:
- 168 - Start at Power Up - Enabled
- 169 - Flying Start - Enabled
- 184 - Power Loss Mode - Continue
- 185 - Power Loss Time - 60.0 seconds
- 186 - Power Loss Level - 0 vdc
- 238 - Fault Code (undervoltage) - Bit 1 - 0
- 238 - Fault Code (decel inhibit) - Bit 6 - 0

These are the only 2 drives that use 2 DI's for speed control to preset speeds...


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## glen1971 (Oct 10, 2012)

Hybwolf said:


> P093 speed reference B = "preset speed 1"
> P101 preset speed 1 = 30 hz
> P102 preset speed 2= 60 hz
> P361 DI1= 15 speed select 1
> ...


What about P090 (Speed Ref A)? It is currently set at 17 (Preset Speed 7)...

Do the parameters 15 and 16 on the 361-366 parameters line up with the preset speeds? I tried to make heads or tails out of the logic table, but started to lose my mind on it... It's on Page 3-60, note 1 in the User Manual...


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## Cow (Jan 16, 2008)

If the preset speed inputs come from the PLC, is it possible to set a short time delay after power comes back online, before the PLC sends the run and preset speed signals to the drives? This would give the drives a chance to come online. 

I'm just getting into PLC's myself, and the last two projects I programmed, I had a phase monitor relay tied to a PLC input to kill all the equipment if power was interrupted. I then had a 10 second startup delay for all the equipment after the phase monitor showed power was restored.


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## glen1971 (Oct 10, 2012)

Cow said:


> If the preset speed inputs come from the PLC, is it possible to set a short time delay after power comes back online, before the PLC sends the run and preset speed signals to the drives? This would give the drives a chance to come online.
> 
> I'm just getting into PLC's myself, and the last two projects I programmed, I had a phase monitor relay tied to a PLC input to kill all the equipment if power was interrupted. I then had a 10 second startup delay for all the equipment after the phase monitor showed power was restored.


Good idea, but I'm not sure that PLC programming is in the cards.. That gets into a fair amount of paperwork and probably wouldn't happen quickly.. And if I was to do this change, personally I'd get the client to add run status from the drives to the PLC, so they can tell on the plant HMI actual run status or faults..(Another matter.. lol...)


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## Hybwolf (Jul 31, 2011)

glen1971 said:


> What about P090 (Speed Ref A)? It is currently set at 17 (Preset Speed 7)...
> 
> Do the parameters 15 and 16 on the 361-366 parameters line up with the preset speeds? I tried to make heads or tails out of the logic table, but started to lose my mind on it... It's on Page 3-60, note 1 in the User Manual...


P090 (speed ref A) is set when no speed select inputs are high and the default setting will use Analog In 2 as the speed reference .With this parameter set to "17", if neither DI1 or DI2 is high, the drive will select the speed that is programmed into paramter P107 "preset speed 7" instead. 

Preset speed 2 is automaticaly referenced when speed select 2 is high.


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## glen1971 (Oct 10, 2012)

Hybwolf said:


> P090 (speed ref A) is set when no speed select inputs are high and the default setting will use Analog In 2 as the speed reference .With this parameter set to "17", if neither DI1 or DI2 is high, the drive will select the speed that is programmed into paramter P107 "preset speed 7" instead.
> 
> Preset speed 2 is automaticaly referenced when speed select 2 is high.


Ok.. So if I'm understanding correctly, leave Speed Ref A at the default of Analog 2 and set the rest as you outlined earlier.. Then when the drive goes to look for a speed, it will take the two programmed in Preset 1 or 2? Does it need to see a "run" input as well?


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## Hybwolf (Jul 31, 2011)

glen1971 said:


> Ok.. So if I'm understanding correctly, leave Speed Ref A at the default of Analog 2 and set the rest as you outlined earlier.. Then when the drive goes to look for a speed, it will take the two programmed in Preset 1 or 2? Does it need to see a "run" input as well?


You need a run input to tell the drive to start and you also need to tell the drive what speed to run at. So with a run input and DI1 high and DI2 low,the drive will run the motor at 30hz, with DI1 low and DI2 high, the motor will run at 60hz.

With neither DI1 or DI2 high ,the motor will run at what ever is programmed into speed preset 7,Parameter 107 unless you change Parameter 90 back to the default setting- analog in 2


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## glen1971 (Oct 10, 2012)

Hybwolf said:


> You need a run input to tell the drive to start and you also need to tell the drive what speed to run at. So with a run input and DI1 high and DI2 low,the drive will run the motor at 30hz, with DI1 low and DI2 high, the motor will run at 60hz.
> 
> With neither DI1 or DI2 high ,the motor will run at what ever is programmed into speed preset 7,Parameter 107 unless you change Parameter 90 back to the default setting- analog in 2


Ok.. The way it sits now, the run input comes from the local switch and a vibe switch in series with it. When the station switches to generator, and back to utility, both the run and either DI1 or DI2 come in at the same time, and the drive doesn't always restart.. Is there a delay, or a parameter change, that I need to make so that both can come in at the same time, and the drive with restart?


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## glen1971 (Oct 10, 2012)

So as an update...
I changed parameter 090 (Speed Ref A) to "2" (Analog In2).. Left the all the other parameters as was... Tested it to the generator, and back to utility and everything worked out as it should... The only issue was the "run" lamp, driven from the drive's run DO, was on at 0 Hz, which I can get my head around how the run bit is wired (On/Off switch through a vibe switch).. 
Woulda been handy to have had that fix last Thursday, as the 160 kmh winds we had over the weekend caused a few nuisance trips on the site with the power fluctuations...
On another positive note.. I reread the data table associated with the Digital Inputs and now makes perfect sense how it's laid out... Musta been the cold I'm fighting had my brain in the "fuzzy mode"....


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