EB-60X Installation & Service Manual |
Motor Data Package
b) The required OFF time for a given ON time is found from (EQ-2).
toff = - TCTP 1n 1 -
/ TCTP
-ton
1 - e
Tc
2
TOUT
2
-ton
*
t
ON
= 4 sec
TCTP = 16 min.
60 sec/min = 960 sec
t
OUT
= 47.1 lb-ft
Tc = 18.0 lb-ft
1-
toff = - 960 sec 1n
47.1
-4/960
1 - e
18.0
2
-4 sec
(
() )
t
OFF
= -960 sec 1n 0.9383 – 4 sec
t
OFF
= 23.7 sec
For the EB-606-C motor operating at the load point in this example, an ON time of 4 sec must
be followed by an OFF time of 23.7 sec. so as not to exceed its thermal limits
.
Example #2
The motor of Example #1 is running at 2500 rpm with an intermittent operating torque of 61.2
lb-ft.
FIND:
a) max. ON time
b) required OFF time for an ON time of 4 sec.
(a) Given T
OUT
= 61.2 lb-ft
From performance curve EB-606-B
Tc at 2500 rpm = 22.2 lb- ft.
From Specifications CD-27028:
TCTP = 16 min.
Using EQ-5 and above values:
t
MAX
= 2.3 min.
(b) Using (EQ-2) and an ON time of 4 sec, an OFF time is:
t
OFF
= 27.1 sec.
Содержание EB-9207
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