Laserfiche WebLink
Chapter 4 — System Installation <br /> Page 4 -11 <br /> REV. 3 <br /> Remove the gas valve cover and thread the stainless steel A tee pulley that is used to close two (2) gas valves can <br /> cable through the conduit back to the control head. Thread only be used to close gas valves with similar stem travel. <br /> the cable through the hole in the gas valve ratchet wheel. Gas valves from 3/4 in. up to 1 1/2 in. can be used on the <br /> The line must then be crimped, and the crimp positioned same tee pulley. A 2 in. gas valve can be used only with <br /> inside the center of the ratchet wheel. another 2 in. gas valve. Gas valves from 2 1/2 in. up to 3 in. <br /> can be used on the same tee pulley. As an example, using a <br /> At the gas valve, loop the cable through the valve stem and 3/4 in. gas valve with a 3 in. gas valve will not allow the 3 in. <br /> secure it with the crimp provided (see Figure 4 -18). valve to fully open. <br /> • Note: See Chapter 2 — Components for maximum dimen- CAUTION <br /> ■ sion to extend valve stem. <br /> The tee pulley must never be used to connect multiple <br /> The gas valve line can now be put into a set position by fusible link lines to a single control head. <br /> applying tension to the gas valve line. This is accomplished <br /> by using a 1/2 in. hex wrench on the gas valve ratchet <br /> wheel. The ratchet wheel will be ratcheted in a clockwise f „ /r:! <br /> direction until the gas valve is fully open. Secure the gas ,■ L .!1 <br /> valve cover plate to the gas valve box with the four (4) lUII <br /> screws provided. The gas valve line is now in a set position. <br /> See Figure 4 -19. <br /> CRIMP <br /> 1 121N. MIN. <br /> CAUTION 30.5 cm) <br /> Overtightening the gas valve may cause the system a --L <br /> not to actuate. <br /> Figure 4 -20. Tee Pulley Installation. <br /> li t 002B88PC <br /> ton <br /> a:; '~ MICRO SWITCH INSTALLATION <br /> IMF ' - ' <br /> �'� ► See NFPA 72, "National Fire Alarm Code," Initiating Devices <br /> ty _ r la section, for the correct method of wiring connection to the fire <br /> alarm panel. <br /> GAS VALVE <br /> CONNECTION SE The Model MS -SPDT, MS -DPDT, MS -3PDT, or MS -4PDT <br /> Micro Switch is available for use where an electrical output <br /> Figure 4 -19. Gas Valve Line Termination. is required. These switches can be field installed in the con - <br /> 002887PC trol head. See Figure 4 -21 and Figure 4 -22 and refer to <br /> Instruction Sheet, Part No. 551159, included with switch <br /> 2. Electrical Gas Shut-Off Valve Installation, shipping assembly, for detailed mounting instructions. <br /> E_ECTRICAL BOX <br /> The Model MCH3 /ECH3 /NMCH3 Control Head is used to ` (SUPPLIED BY OTHERS) <br /> operate the electrical gas shut -off valve. This valve is locat- 1r1 <br /> ed in the fuel gas supply line. The valve body has an arrow ,...; <br /> I�� t <br /> which indicates direction of gas flow through the valve. A f t0 ? 4 <br /> pi tr <br /> reset relay must always be used with an electrical gas shut- .�"'_"I`-' w' - <br /> ` ti. <br /> �� �r <br /> ��, !Ai <br /> valve. For proper wiring of the electrical gas shut -off ■"- -' <br /> valve, see Figure 4 -15. <br /> TEE PULLEY INSTALLATION <br /> The Model TP -1 Tee Pulley is used to connect two (2) Figure 4 -21. Micro Switch Installation in Model <br /> mechanical gas valves or two (2) remote mechanical pull MCH3 /NMCH3 Control Head. <br /> stations to a single control head. The cable proceeding from 902889PC <br /> the control head must always enter the branch of the tee <br /> pulley. See Figure 4 -20. <br /> ULEX 3437 CEx732 <br /> September 1, 2006 <br />