High/Low Speed Pot Selector

ALLEN-BRADLEY
ALLEN-BRADLEY
BULLETIN 1336 PLUS
HIGH/LOW SPEED POT SELECTOR
APPLICATION NOTE # 1336S - 13
June 24, 1997
PURPOSE
The purpose of this document is to provide guidelines for wiring and control
schemes for the Bulletin 1336S AC Drive. This document is to be used as a
suggestion only. Users must ensure that installations meet applicable codes and
are suitable for the existing conditions.
The Bulletin 1336S User Manual should be used as a reference to ensure that
proper wire selection, routing and fusing guidelines are followed.
WHAT THIS NOTE
CONTAINS
The Bulletin 1336S remote speed pot can be configured for a HIGH/LOW function
with the use of a selector switch and fixed resistors. This allows the User to switch
from a LOW speed to HIGH speed with the switch and still utilize the POT to trim
the speed.
INTENDED
AUDIENCE
This application note is intended to be used by personnel familiar with the
hardware components and programming procedure necessary to operate the
Bulletin 1336S.
WHERE IT
IS USED
The diagrams, parameter settings and auxiliary hardware used in this application
note are designed to address specific issues in many different applications. Some
changes by the User may be necessary to apply the concepts of this document to
a specific application.
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DESCRIPTION
The addition of two fixed resistors is necessary to create an
offset
for
the
HIGH/LOW function. The following operating frequencies are based on a drive
minimum frequency setting of zero hertz and a maximum of 60 HZ. Installing a
10K ohm resistor between TB2 terminal 1 and the high end of the speed pot will
create a maximum frequency of 33HZ when the remote speed pot is fully CW.
Installing the 10K ohm resistor between TB2 terminal 3 and the return of the
speed pot will create a minimum limit of 33HZ. To complete the circuit,
a
2position selector switch is utilized to select which resistor is in the circuit.
With the switch in the LOW position, the resistor between TB2 terminal 1 and the
speed pot will cause a voltage drop resulting in a frequency range from 0-33HZ.
When the switch is set to the HIGH position, the resistor between TB2 terminal 1
and the speed pot is bypassed with the switch. The other resistor is pulled into the
circuit between TB2 terminal 3 and the speed pot return. This resistor will cause a
voltage drop after the pot creating a frequency range of 33-60HZ. Refer to figure 1
for diagram.
Overlapping contacts on the selector switch are not required for this application. A
3-position selector may be used to offer a MID speed. The MID setting would open
both sets of contacts. The frequency range will be from 23-46HZ.
APPLICATION
CONSIDERATIONS
When operating in the LOW speed mode the full range of the speed pot can be
utilized. In the HIGH speed mode the speed pot must not be turned fully CW or an
OPEN POT FAULT will occur. The speed pot should be limited to a 340 degree
maximum turn.
The recommended wattage value for the fixed resistors and potentiometer are 2
watts.
PARAMETER
SETTINGS
Number
7
8
10
Group
Setup
Setup
Setup
Name
Freq Select 1
Accel Time 1
Decel Time 1
Value
1=Remote Pot
0-600 Sec
0-600 Sec
The acceleration and deceleration times set in parameters 7 and 8 determines the
rate of change in frequency between the minimum and maximum frequency
settings.
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FIGURE 1 HIGH/LOW SPEED POT
115V AC
R
S
T
GND
TB1
TB2
BULLETIN 1336PLUS
1
POT HIGH
2
POT LOW
3
POT/SIGNAL COMMON
4
5
0-10V INPUT
6
4-20MA INPUT
7
PULSE INPUT (-)
8
PULSE INPUT (+)
9
METER OUTPUT
10
JUMPER J5
CR1
11
1-2 (4-20ma)
CR2
3-4 (0-10vdc)
12
13
CR3
14
CR3
15
16
CR4
17
CR4
18
115VAC INTERFACE
TB3
START
19
TB3
INPUT 1
ENCODER B
31
STOP
EXT FAULT
INTERLOCK
CUSTOMER
INTERLOCK
20
STOP
ENCODER A
32
21
COMMON
ENCODER B
33
22
INPUT 3
ENCODER A
34
23
INPUT 4
ENC. +12V
35
24
INPUT 5
ENC. COMM
36
25
COMMON
26
INPUT 6
27
INPUT 7
28
INPUT 8
29
COMMON
30
ENABLE
INPUT MODE 2
TB1
U
V
W
GND
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