Emerson 2468CB Weather Radio User Manual


 
Hydrastep 2468CB and 2468CD Manual Delay Relay Output Board Option
24685034
3b-3
3B.1 GENERAL DESCRIPTION
The Delay Relay Output Board (PCB 24680509) is mounted on top of the input board using 3
nylon spacers. Electrical connection between the two boards is via plug and socket (SK1 on
the input board and PL1 on the delay relay output board).
A second delay relay output board may be mounted on top of the first on nylon spacers.
Holes have been drilled on all delay relay output boards to receive the 3 nylon spacers. The
top output board is offset towards the centre of the unit improving the cable layout from the
delay relay output boards. The nylon spacer fixing holes and mounting holes are illustrated
in Figure 3b.1 (on page 3b-6).
Each of the four delay relays can be energised by any one of up to 16 electrodes, with an
individual choice of being energised when its selected electrode is in steam or is in water.
Furthermore, relay RL1 can be used to monitor an electrode state or to register an ALARM
condition. When set to register the ALARM state, the relay is energised in the ‘system
normal’ state and de-energises when an ALARM condition exists.
Each relay channel also contains a delay circuit where set delays of between 0 and 23
seconds can be provided using one of four split pad links. Provision is also made by split
pad links, to bypass each delay circuit. The split pad linkage is fully covered in section 3b.3
of this chapter.
This option comes complete with the nylon spacers and two 8-way output sockets.
3B.2 INSTALLATION
This sub-section deals with the mechanical and electrical installation of the Delay Relay
Output Board (PCB 24680504) option. In the rest of this chapter the ‘delay relay output
board’ title is shortened to ‘output board’.
3B.2.1 STORAGE & PRE-INSTALLATION INSPECTION
3b.2.1.1 Storage Area
The storage area must be dry, dust-free and kept at a reasonable temperature. The storage
area should allow for access and inspection of all items of equipment.
3b.2.1.2 Pre-Installation Inspection
Open the option package and inspect the contents for signs of damage. Check contents for
completeness.