19 



c. An "on-off" switch is to be provided to energize or de-energize the 

 complete unit. A locking device should be provided to prevent tampering with 

 this switch. 



d. The chart drive should have the following controls (listed here in 

 the order in which they take precedence): 



i. Manual "on-off" switcn 



ii . Manually set timer for continuous operation up to 



an interval of 2 hours. (This would bypass Switch i.) 



iii. Automatic control which will actuate the chart drive 

 for a predetermined period of time every hour, or 

 other preselected interval, unless bypassed by the 

 preceding switches. 



6- The contractor is to furnish plans and an instruction book with the 

 equipment . 



