File $Source: /home/juda/www/hrc_flight/macros/RCS/off_to_i.html,v $

Version $Revision: 1.2 $

Last Update $Date: 1999/04/21 20:15:26 $

HRC CCB Status Approved

OP03 Procedures op03:

HRC Higher-Level Sequences

HRC Off to Operational HRC-I

Description:

This higher level sequence takes the HRC from a powered off state to one with an fully operational instrument with the HRC-I selected as the detector in use. As an example of when it might be used, this procedure would be executed after exiting an eclipse that had required a shedding of the HRC power load.

It is assumed that the HRC power configuration has already been configured (Power Configure HRC to use CEA A) and that the HRC Primary Bus power has been switched on. The HRC Power-up sequence is executed, followed by the sequence to switch to telemetry format 1 if necessary. Next executed is the sequence that sets the HRC-I unique defaults. The anticoincidence shield PMT HV is turned on and ramped to its operational level. Finally the HRC-I MCP HV is brought into operation if desired; the method depends on whether the HRC is at the aim-point of the HRMA and if not, whether the ramp-up should be done manually or autonomously.

Cautions/Restrictions:

The HRC-I MCP HV must not be ramped up if the HRC is in a region of high radiation (see HRC-R-002) or if the detector housing pressure is greater than 10^-5 torr (see HRC-C-002).

The stored command sequence to turn on the HRC-I MCP HV must be in the enabled state. If it has been disabled in response to an EPHIN trigger, the radiation environment must be verified as safe before we can proceed. The stored command sequences to ramp the HRC-S MCP HV up and down must be disabled.

Procedure

Power Up HRC on CEA A - SCS #69 (power-up.html)
If telemetry format = 1 execute the following sequence
- Select HRC Observing Mode Telemetry (obs_mode.html)
Set HRC-I Unique Defaults (i_unique.html)
If operating autonomously execute this sequence
- Antico. Shield 1 Auto On and Ramp-up (sh1_on_and_up.html)
Else run the manual sequence
- Antico. Shield 1 Manual On and Ramp-up (sh1_act.html)
Disable SCS #88 "HRC-S MCP HV Ramp-down"
Disable SCS #90 "HRC-S MCP HV Ramp-up"
Enable SCS #87 "HRC-I MCP HV Ramp-down"
Enable SCS #89 "HRC-I MCP HV Ramp-up"
If the HRC-I MCP HV is to be turned on
- HRC-I MCP HV On - SCS #92 (i_mcp_hv_on.html)
- If the HRC is at the HRMA aim-point
  - Activate SCS #91 - HRC Dither Control
- Else
  - If operating autonomously execute this sequence
    - HRC-I MCP Auto HV Ramp-up - SCS #89 (i_mcp_hv_up.html)
  - Else run the manual sequence
    - HRC-I MCP Manual HV Ramp-up (man_hv_up_i.html)

$Log: off_to_i.html,v $

Revision 1.2 1999/04/21 20:15:26 juda

Added logic branch for MCP HV turn on and clarified MCP HV operation in description.

Marked as Approved

Revision 1.1 1999/03/03 21:36:07 juda

Initial revision

Revision 1.2 1998/12/15 17:10:15 juda

remove procedure steps to set telemetry formats other than format 1 -- added logic branch for case with HRC at HRMA aim-point -- added HTML page names to link names in procedure list

Revision 1.1 1998/10/14 14:30:09 juda

Initial revision

Dr. Michael Juda
Harvard-Smithsonian Center for Astrophysics
60 Garden Street, Mail Stop 70
Cambridge, MA 02138, USA
Ph.: (617) 495-7062
Fax: (617) 495-7356
E-mail: mjuda@cfa.harvard.edu

File	$Source: /home/juda/www/hrc_flight/macros/RCS/off_to_i.html,v $
Version	$Revision: 1.2 $
Last Update	$Date: 1999/04/21 20:15:26 $
HRC CCB Status	Approved