PowerTec Digimax, Installation And Operation Instruction Manual

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Page 6 © copyright 1992-1996 by Powertec Industrial Motors
4 CATHODES OF CONTROL INPUTS (ground or common)
5 RUN INPUT (+24 VDC)
6 PRESET INPUT (+24 VDC)
7 EMERGENCY STOP INPUT (+24 VDC)
8 REVERSE INPUT (+24 VDC)
9 JUMP/MOP UP INPUT (+24 VDC)
10 JUMP/MOP DOWN INPUT (+24 VDC)
Power for the control inputs must be supplied from a separate source. Usually this
power comes from the Brushless drive being controlled. Nominal supply voltage is 24 VDC,
which need not be regulated, but must be filtered. The tolerance is +/- 25%.
The control inputs do not control any functions on the controlled drive. Commands
given to the DIGIMAX DIGIMAX DIGIMAX DIGIMAX DIGIMAX
®
must also be given to the drive at the same time.
The EMERGENCY STOP input must be activate before the unit will respond to any
external input or keyboard commands. This input normally parallels the E.STOP of the drive.
Activating the RUN input starts the DIGIMAX
®
, and will it run until the RUN input is
removed. Usually, the run relay contact on the speed board of the drive is used for this. A
SETPOINT value should be entered prior to the first time a RUN command is entered after
power is applied; otherwise the unit will start at zero speed (or ratio) and wait for a SETPOINT
to be entered by the operator. If parameter #14 is set to 1 (see page 18), on all subsequent
RUN commands, the DIGIMAX
®
will start at the last speed or ratio entered.
The PRESET command changes the speed output to go to the value in parameter #9.
The REVERSE input causes the frequency output to decelerate, at the rate set into
parameter #7, to zero speed, and then to accelerate back to the setpoint at the rate set into
parameter #6. Giving a reverse command to the DIGIMAX DIGIMAX DIGIMAX DIGIMAX DIGIMAX
®
does NOT cause the drive to
reverse. A separate, simultaneous command must be given to the drive. If the drive is given
a reverse command, it will not reverse until the DIGIMAX DIGIMAX DIGIMAX DIGIMAX DIGIMAX
®
is given a reverse command,
because the drive input frequency must be at zero before the drive will reverse direction.
The JUMP/MOP UP and JUMP/MOP DOWN inputs duplicate the functions of the UP
and DN inputs on the front panel.
11 - TACHOMETER INPUT
12 + TACHOMETER INPUT
13 - FOLLOWER INPUT
14 + FOLLOWER INPUT
These two inputs are isolated from the DIGIMAX DIGIMAX DIGIMAX DIGIMAX DIGIMAX
®
electronics and from each other.
Both inputs require a +24VDC nominal peak input and a low of less than 1VDC. Both inputs
will accept signals up to 50 kilohertz. Minimum pulse width for both inputs is 10 microsec-
onds. Wider pulse widths are desireable. Rise times are not critical, but they should be less
than 5% of the duty cycle.
The tachometer input is for the DIGIMAX DIGIMAX DIGIMAX DIGIMAX DIGIMAX
®
display and it also supplies a zero speed
signal. It normally comes from the motor control, but it may come from any frequency
reflecting the driven process. With a 1750 RPM small frame motor, a standard POWER TEC
Brushless motor control supplies a 3500 Hertz pulsed waveform to this input, but larger
motors' controls supply a 7000 hertz signal to the tachometer input and servo rated controls
may supply frequencies of up to 50 kilohertz.
The follower input is the frequency which the DIGIMAX DIGIMAX DIGIMAX DIGIMAX DIGIMAX
®
follows in SLAVE mode. A
standard 1750 RPM low horsepower Brushless motor control operates at 3500 Hertz input
frequency. This is the ideal input frequency for the follower input if the follower motor is 1750
RPM. The DIGIMAX DIGIMAX DIGIMAX DIGIMAX DIGIMAX
®
can multiply by a factor of up to eight, but performance and resolution
at high multiples may be degraded.