VFD Noob, Hitachi J300 input confusion

[Aerik]

Got a great deal on a Hitachi J300 inverter, using to control a 5hp gear motor for feedworks on a planer.. need to use the forward, reverse, free run stop, and jogging.. also control speed via 1K ohm pot..

I have the pot connected and working, but.. the inputs for FWD/REV/JG/FRS arent working as described in the manual:

http://www.hitachi.us/supportingdocs/forbus/inverters/Specifications/J300U_Instruction_NB506XC.pdf

all inputs are set up for a NO connection, and needs a 24V input for 20ms, however, when the 24V is supplied, it wont 'pick up' the input, and the 24V needs to stay supplied at the input for continued operation.. this is the same for all inputs, FWD, REV, JG and FRS..

other inverters I have here dont require a closed connection, and from what I can tell from the J300 documentation, that should be the case with this inverter as well..

any help would be greatly appreciated.. probably something in the programming I'm overlooking, or a flaw in my external circuit? at this point I'm just benching it and using a jumper from the internal 24V supply to the inputs.. anyhow, thanks in advance!

 

[ozmosis]

Page 5-5 of the maunal you posted shows the connection of either sink or source. Sink is the factory default and requires a jumper between P24 and PLC. Have you got this? Alternatively you use the P24 source and drop this into the Digital inoputs.Looks like you need to link PLC to CM in the diagram for this to work.
Not too familiar with the Hitachi J300 but I think this could be where your problem lies.

 

[Aerik]

Yep.. I've tried it both ways actually, sink and source. the inputs just wont pick up the 20ms signal

I'll keep poking around until I get it to work, and will keep the topic updated

any other ideas would be greatly appreciated!

 

[electricpete]

I thought the correct spelling was "newb"

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[itsmoked]

electricpete! Don't be a noob!

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[jraef]

Funny, I don't know of ANY drives who's inputs only require momentary connection. You can DESIGN a 3 wire input system for any of them, but the inputs themselves are always momentary. Are you sure you are seeing what you think you are seeing on the other drives? In other words, you will need to design a control circuit, usually in programming or by using an output relay, to "seal in" a momentary command to the FWD or REV inputs. Stop commands are almost always momentary from an input function, but held closed in the real world so that they are fail-safe.

 

[Shozza]

Kind of a late reply to this thread but if you look at page 5-14 of the manual it shows the terminal connection diagram. If you look at the digital inputs you'll notice they're latched inputs. This looks to be fairly common throughout the entire Hitachi range and is fairly common with other manufacturers as well. A lot of drives offer the functionality of 3-wire control by changing a parameter and assigning a digital input to a 'stop' function but unfortunately the J300 doesn't seem to.