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Can I connect a PTC probe to an ATV11, ATV12 , ATV21, ATV312 , ATV31, ATV32, ATV61 or ATV71 variable speed drive?

IF YOU ARE USING ANY OF THE DRIVES IN A ATEX AREA YOU CANNOT USE THE
PTC INPUT OF THE DRIVE YOU MUST USE AN ATEX APPROVED UNIT
 
ATV11, ATV12 and ATV312 (or ATV31) drive ranges

ATV11, ATV12, ATV31 and ATV312 drives do not include the motor thermal monitoring function via PTC probe. However, this function can easily be provided by a dedicated monitoring module.
See the LT3S range of thermal protection units with PTC thermistor probes (these units are NOT ATEX APPROVED).
Connection recommendations for probes:
Check that the motor probes are PTC technology, not PT100 - the LT3S range only works with PTC probes.
Check that the motor has 3 probes wired in series in the motor providing a total of 750 ohms at 20°C.
If the motor only has single-resistor probes (surface probe), the probes on 3 motors can be wired in series and connected to a single LT3S.  
 
See the information on LT3 modules at the end of the document.
On the ATV11’s or ATV12’s you will have to inhibit the control or power circuit or both using the output from the LT3S as there is no external fault parameter.
Where as on the ATV31 and ATV312 you would use the no – volt output contact of the LT3S and connect it across +24 V and LIx. Then in the FLt- menu you select EtF and set that for the input LIx on which you have connected the LT3S.
As the out put from the LT3S is a Normally Closed contact you will have to change the configuration of the fault still in the FLt- menu this time parameter LEt is changed from HIG to LO so the fault is active when the input changes to 0V.                          

ATV61 and ATV71 drive ranges
Thermal monitoring via PTC probes is provided on ATV61 and ATV71 drives by specific inputs.
Common characteristics of these inputs
Nominal value < 1.5 kohms: This corresponds to a maximum of 6 probes (250 ohms at 20°C) or to two sets of 3 (sometimes prewired in the motors).
Trip resistance 3 kohms
Reset value 1.8 kohms
Short-circuit protection < 50 ohms

Location of the inputs

Input LI6 on the terminal block: Wire the PTC probes between terminals LI6 and 0V; this input is seen as a PTC input if switch SW2 is set to PTC.
Input TH1+/TH1- on the VW3A3201 option card
Input TH2+/TH2- on the VW3A3202 option card

Settings
The parameter setting will differ according to the PTC input selected:
Input LI6
In the menu [ 1.8 Fault Management ] (FLt-) you select the input as LI6 = PTC probe which is only accessible if SW2 is set to PTC. Then you choose from the options below which one meets you application
 
No: Input not used (factory setting)
Always: PTC probe faults are monitored continuously, even when the power section is off (provided the control section power is on)
Power ON: PTC probe faults are monitored when the drive's power section is supplied with power
Motor ON: PTC probe faults are monitored when the motor power is on

Input TH1+/TH1-
In the menu [ 1.8 Fault Management ] (FLt-) you select the input as PTC1 probe, which is only accessible if the options card VW3A3201 is fitted. Again you choose from the options below
 
No: Input not used (factory setting)
Always: PTC probe faults are monitored continuously, even when the power section is off (provided the control section power is on)
Power ON: PTC probe faults are monitored when the drive's power section is supplied with power
Motor ON: PTC probe faults are monitored when the motor power is on

Input TH2+/TH2-

In the menu [ 1.8 Fault Management ] (FLt-) you select the input as PTC2 probe, which is only accessible if the options card VW3A3202 is fitted
No: Input not used (factory setting)
Always: PTC probe faults are monitored continuously, even when the power section is off (provided the control section power is on)
Power ON: PTC probe faults are monitored when the drive's power section is supplied with power
Motor ON: PTC probe faults are monitored when the motor power is on

Faults generated by probes:

Motor overheating
Probe break fault
Probe short-circuit fault
ATV32 range.
The ATV32 range can have only one set of PTC’s fitted at LI6 and COM and the program is the same as for 61 and 71

 
ATV21 drive range
Thermal monitoring via PTC probes is possible using the VIB analog input.
Wiring
Wire a 3.3 kohm ¼ Watt resistor between terminals PP and VIB, then wire the 3 probes in series between terminals VIB and CC.
Parameter setting

Set parameter F645 to 1 or 2 (both these values convert VIB to a thermal probe input)
F645 = 1 (default mode: OH2 alarm and drive stopped) 

F645 = 2 (alarm only mode: OH2)

Set F646 to the PTC threshold detection value

More information
 
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