Wooding wrote:
I've got a Mitsubishi FR-S500 inverter (actual model FR-S520S) that I
want to use to control the speed of my milling machine (metal content
bit). I've jury-rigged it to use the setting dial to control the motor
speed and its working fine. I can control the speed from barely moving,
right up to twice normal speed.

I've wired up a remote switch to start, stop and reverse the motor as
shown in section 1.7.1 of the detailed instruction manual
[IB(NA)-0600027] under the heading "Two-wire type connection (STF,
STR)", but it doesn't work. Connecting SD to STF or STR has no apparent
effect at all. I've tried it in PU and EXT mode, and still nothing.
The only parameters changed from the factory settings shown in the
manual are...
P1 100
P7 0.5
P8 0.5
P30 1
P53 1
Can anyone help please?

Thanks to those who responded.
The problem is now solved. Although the manual was quite explicit about
the size of the flat-bladed screwdriver needed to tighten the terminals,
it was particularly coy about what terminals to connect. The wiring
diagram shows SD as the common input, but hidden away in another section
of the manual is the important note that SD is only the common input
when using SINK logic. Here in UK it is wired to use source logic and
the common input is changed to PC. With P79 set to 3 and PC as the
common input it now works fine.
Ned was quite right - "The Mitsubishi drives are very good, but the docs
are awful."

--

Regards, Gary Wooding
(To reply by email, change feet to foot in my address)