PowerTec DFS-1 manual Frequencyoutputdigital Inputs

FREQUENCYOUTPUT:DIGITAL INPUTS:

There are two outputs available to supply a frequency for external use.

The first is located at TB2:B terminal 10 (+) and 11 (-). This is an output which is intended to provide

areference frequency input for another DFS-1, BCDMAX or CRM-1. This output is not compatible with the DIGIMAX. It will provide a signal of +/- 1.5V minimum when connected to another DFS-1's reference frequency input. This output on a unit configured as a master, operates at 16 times the frequency of the motor speed output reference. There is a 120 ohm termination resistor built into the output for transmission line termination.

When operating the DFS as a slave, the output frequency is internally divided by 16 in addition to being multiplied by the set ratio from the slave. As a consequence, the frequency output from a DFS slave cannot be used as the reference to another DFS slave without some way of first multiplying this frequency by 16. POWERTEC’s Cascade Ratio Multiplier option board (4001-153430-XXX) can be used for this purpose. Contact the factory for any frequency following application which requires a reference source other than a master DFS.

The other frequency output is at TB2:B13. This is a 24VDC peak square wave referenced to the DFS- 1 common (TB2:B14). This signal is at the motor speed output reference frequency and may be used to interface with a DIGIMAX or a BLDC motor control. This output sources a maximum of 10mA and can sink 30mA.

There are eight digital control inputs on TB2:A as well as a +24VDC supply (TB2-A14) and com- mon (TB2-A1). The eight inputs are optical isolator input diodes with a common cathode connection at TB2-A2. When the +24VDC, DFS-1 supply is used to power the inputs, TB2:A2 must be jumpered to the 24VDC common terminal on TB2:A1.

The functions of all inputs are programmable except Emergency Stop (TB2-A3). All digital inputs are electrically isolated from the DFS-1 power supplies and common when an external power supply is used to power the digital inputs (such as from a PLC).

The default parameter setup is for a set of standard motor controller input connections on TB2:A terminal strip (see figure 3 on page 3).

Five of the inputs are set up for standard push- button operation of the DFS-1. They are:

Run	4 (+)
Preset	5 (+)
UP (increase)	6 (+)
DOWN (decrease)	7 (+)
Reverse	8 (+)

All of these inputs are referred to TB2-A2. Note that TB2-A2 (the common cathode connection) must be jumpered to common (TB2:A1) in the basic connections.

Each of these inputs will take a +24VDC input (no more than 30VDC, not less than 18VDC). If an external source of +24VDC is used, TB2-A2 on the upper level must be connected to the negative side of the external source.

Mode of Operation:	differential
Number of receivers:	32 maximum
Maximum Cable Length:	4000 feet
Maximum Frequency:	10 Megahertz
Common Mode Voltage:	+12V, -7V
maximum
Driver Output:	+/-1.5V minimum
Driver Load:	60 ohm minimum
Driver Short Circuit: 1	50 mA to ground
Driver Output Resistance:	120 ohms (ON)
Receiver Input Resistance:	12 Kohms
Receiver Sensitivity:	+/-200 mA

B

Figure 5: Slaving DFS-1 units with the Reference Frequency Output.

Page 10	DFS-1 Manual	Revised 7/95
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