Littelfuse 75920 Serie Instrucciones De Instalación

Installation Instructions
75920 Series Master Disconnect Switch
Part Numbers: 75920, 75920-01, 75920-03, 75920-05, 75920-10,
75921-02, and 75921-10
Description
The 75920 Master Battery Disconnect switch is designed
to protect service personnel and your vehicle systems. The
switch protects vehicles from both battery drain and theft as
well as allowing service personnel to lock-out tag-out. It also
serves as an effective emergency power cutoff.
Specifications Overview
Operating Voltage:
Approvals:
Continuous Current:
Intermittent Current:
Operating Temp:
Ingress Protection:
Panel Thickness Range:
Corrosion Test:
Vibration and Shock Test:
Mounting Stem:
Knob Retention Screw Torque: 7.0 in-lbs +/- 2.0 in-lbs
Web Resources
Download 2D print and technical resources at:
littelfuse.com/75920
© 2020 Littelfuse Commercial Vehicle Products
littelfuse.com
6V min, 36V max
Ignition Proof to ISO 8846
Meets or Exceeds UL 1107
12V: 400A max
24V: 300A max
36V: 200A max
12V: 1000A
90 sec on, 5 min off
12V: 1500A
60 sec on, 5 min off
12V: 2000A
30 sec on, 5 min off
12V: 3000A
15 sec on, 5 min off
-40 to +85 °C
IP67 per IEC 529
0.032-0.450" (0.81-11.43 mm)
96 hours - salt spray test
to ASTM standard
SAE J1455
Threads: 3/4"-16
Max Torque: 18 ft-lbs (24.4 Nm)
0.79 Nm +/- 0.23Nm
Installation
This product requires the use of the bezel. It supports the
knob and guides it during operation to assure long life and
smooth operation
1. Open the attached hardware bag and check contents
versus the list on the next page.
2. Put one of the 3/4" hex nuts on the neck and then the
3/4" lock washer. Make sure to run it down far enough to
leave space the get the neck through the panel.
3. Bring the switch in through the back of the panel making
sure to align the anti-rotation stud.
4. Adjust the mounting nut behind the panel until ½ - ¾"of
the threaded portion of the neck (not including the shaft)
extends through the panel.
5. Holding the switch in place, place the bezel over the neck
and align it to the anti-rotation pin.
6. Put the second mounting nut on the threaded neck and
tighten to 216 in-lbs maximum.
7 . Line up the knob with the flat on the shaft, and press it in
place until it bottoms out.
8. Check to make sure that the lockout opening on the
bezel and the lockout opening on the knob line up so
that a padlock shackle can be placed through both in the
off position. If this is out of alignment, remove the knob
and adjust the two mounting nuts until you can align the
bezel and knob.
9. Once satisfied with the fit of the knob use the 4-40 pan
head screw (7 .0 in-lbs +/- 2.0 in-lbs | 0.79 Nm +/- 0.23Nm)
to lock the handle in place. Then press the plug into the
hole with your fingers.
10. Remove the nuts and lock washers from the two
3/8"studs.
11. Place the terminal(s) (attached to an appropriately sized
wire) directly on the base of the stud, as this will assure
the best contact and the least amount of voltage drop
across the connection.
12. Place lock washer over terminal and tighten down nut to
a torque of 70-90 in-lbs.
Make good contact!
Unlike many other Master Disconnects on the market, the
75920 studs are permanently affixed to the base,so you can
remove all the hardware and use the entire stud.
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IF-165 Rev: 010320-C