GE HEALTHCARE
DIRECTION 2307224-100, REVISION 6DISCOVERY LS SYSTEM SERVICE MANUAL
Page 36 Chapter 1 - Preface
1.5    System Lock-Out and Tag-Out (LOTO)
Please follow the current LOTO procedures at the installation site. The instructions that follow are 
general. This manual assumes anyone working on the system is trained to safely LOTO the system 
at the A1 panel, according to the current standards and criteria.
DANGER POSSIBLE ELECTRIC SHOCK WHILE SERVICING HARDWARE WITH 
POWER ON. EQUIPMENT SERVICE CAN ONLY BE PERFORMED SAFELY 
WITH THE MAIN POWER "DISCONNECT" LOCKED OUT AND TAGGED OUT.
DANGER CRUSH HAZARD. UNEXPECTED GANTRY ROTATION CAN CAUSE SERIOUS 
INJURY. NEVER SERVICE THE GANTRY WITH THE AXIAL DRIVE ENABLED. 
USE THE GANTRY ROTATION LOCK TO LOCK OUT AND TAG OUT GANTRY 
ROTATION. SEE SAFETY MENU OF SERVICE DOCUMENT GUI FOR 
APPROPRIATE PROCEDURES.
Follow these general rules:
• Only qualified service personnel trained in the service and operation of this scanner should 
perform any service on this equipment.
• Equipment fuses, switches and circuit breakers are for fire and equipment protection only. 
Do not rely on them to provide protection against electrical shock or un-commanded 
equipment motion.
• Personal Protection Equipment (PPE) is required and must be worn when performing 
service on this equipment. Always use PPE when working with hazardous chemicals or 
materials.
The service switches and circuit breakers described hereafter are not to be relied on as personal 
protection devices. They do not replace LOTO of main power to ensure personal safety. Switches 
and breakers are intended to only inhibit particular system functions and equipment operation. They 
do not eliminate or remove the electrical or mechanical hazards that exist. Because hardware can 
fail and defeat the functionality of these devices, only LOTO ensures protection from unintentional 
gantry rotation and electrocution.
The following are the LOTO safety procedures relating to Thermal, Electrical, Mechanical and 
Gravity energy in the system. Be familiar with these procedures as they are referenced in the 
service procedures when appropriate.
1.5.1    Thermal Energy
When working on the CT gantry system hardware after the system was scanning, it may be 
necessary to wait for up to 60 minutes for the x-ray tube and heat exchanger to cool down before 
touching them. A more specific cooling period for performing service on the tube is found in the x-
ray tube service procedures.