Combination controls CG 10

Transcription

1 Combination controls CG 0... Edition 03. GB

2 Combination controls CG 0 Complete with strainer, two solenoid valves and servo-governor for maximum regulation precision. Special low-noise valves. Optional pressure switch at the inlet. Easy-to-service. All adjustment and metering facilities, with the addition of the electrical connections, are accessible from one side. Flow rate adjustment for precise adjustment of the max. flow rate. Environment-friendly thanks to recyclable and resource-friendly design, plastic parts with material identification. EC type-tested and certified design. Application For safeguarding and controlling atmospheric burners, forced draught gas burners and induced-draught boilers on heating installations up to 0 kw. Combination contro ls CG..G, CG..V and CG..V3 can also be used on steam boiler installations to TR 4. The combination controls are EC type-tested and certified pursuant to the Gas Appliance irective (90/396/EEC) in conjunction with EN 6. CG.. CG.. Single-stage, special-purpose gas heating boilers, single-stage wall heating boilers, pre-mixers. Examples of application CG 0../ CG 0../ CG.. CG.. Hearths. CG.. CG.. Units, single-stage forced draught gas burners, burners with mechanical capacity adjustment. CG 0../ CG 0..G CG 0..V p F CG..G* raught-assisted boilers, modulating or multi-stage control. CG..V Fan and draughtassisted boilers, modulating or two-stage control. CG.. CG.. Radiant plaques, industrial heating systems, radiant tube heaters, space heaters. CG 0../ CG 0..G CG 0..V p F CG..G* Boilers with fluegas, induceddraught fan. CG..V Boilers with fluegas induceddraught fan. * CG..G without connectio n for combustion chamber pressure p F CG..E Boiler with air/gas pre-mixed in the forced draught fan. CG..E Boiler with air/gas pre-mixed after the forced draught fan.

3 CG..G* Forced draught burners, modulating or two-stage control. CG..V Forced draught burners, modulating or multi-stage control. CG 0..G CG 0..V p F Function When the voltage is applied, the two solenoid valves open. The servogovernor achieves a high regulating precision regardless of changing inlet pressures. * CG..G without connection for combustion chamber pressure p F Features solenoid valves, class A or B. CG.. with constant pressure governor. CG.. with constant pressure governor with start load. CG..G with air/gas ratio control, ratio of gas pressure to air pressure :. CG..V and CG..V3 with variable air/gas ratio control, ratio of gas pressure to air pressure : or 3:. CG..E with electronic governor. Inlet pressure switch G..C can be fitted at the works (cannot be fitted retrospectively). With flow rate adjustment. Technical data Types of gas: natural gas and LPG (gaseous). Inlet pressure range p e : to 70 mbar. Ambient temperature: 0 to +60 C. Storage temperature: 0 to +0 C. Threaded connection: Rp / in accordance with ISO 7-. Threaded connection, control lines, p F : Rp /8 (CG..G, CG..V and CG..V3 only) Pressure test points on inlet and outlet. Housing components: AlSi. iaphragms: Perbunan. Strainer: plastic fabric. Solenoid valves (class A or B) with springloaded valve disc, normally closed (when de-energised). Switching frequency: any. Closing time: < s. Mains voltage: 30 V, /+0 %, 0/60 Hz, cos ϕ = 06 V, /+0 %, C voltage 4 V, ± %, 0/60 Hz, cos ϕ = 0 V, ± %, C voltage. Power consumption: A valves: 4 W, B valves: 8 W The electrical power is the same when switching on as in continuous operation. uty cycle: 00 % duty. Protective grade IP 4 in accordance with IEC 9. Fusing: max. 6.3 A, slow-blowing. Electrical connection: Coupler plug in accordance with ISO 4400 with cable gland: Pg. Fitting position In vertical pipework: as required; in horizontal pipework: inclined up to max. 90 to left/right, not upside-down, see also CG..: Function. 0 V~, 4 V~ PE LV V N G..C COM 3 NO PE 06 V=, 0 V= PE +V V +V 3 - V V Type Connection imensions p e max. P Weight N L H* H H3 B B B3 mm mm mm mm mm mm mm mbar VA/W kg CG 0..A Rp / ,4 CG 0..B Rp / , * with rectifier adapter H+ mm H H H* H* H3 M4, 4 mm H3 M4, 4 mm B B L B B3 L CG 0 3

4 CG.., CG.. With constant governor, class C, for high regulating precision, for atmospheric burn ers or single-stage forced draught gas burn ers. Function Both valves open when the volt age is applied. CG..: The outlet pressure rises to. CG..: The outlet pressure initially rises to the start pressure p S. This is then followed by a damped pressure rise to. In fitting position governor point ing downwards, the pressure remains constant for max. 6 sec. when the start pressure p S is reached. Only then does a damped pressure rise to occur. Working range CG..: The outlet pressure can be adjusted by means of a spring from to 40 mbar (CG.. 0:. 0 mbar). CG..: The start pressure p S can be adjusted from to mbar; the outlet pressure can be adjust ed from to 40 mbar (CG.. 0: p S : 7. mbar, :. 0 mbar). p e [mbar] p a [mbar] CG 0../ CG 0.. CG 0.. * * * > p S p S t [s] * Persistence time (steady-state) approx. 6 sec., t [s] only with fitting position governor pointing downwards 4

5 CG..G, CG..V and CG..V3 With constant governor or variable air/gas ratio control, class C, for precise pneumatic air/gas ratio control for modulating or twostage, sliding draught burners or draughtassisted boilers. Function Both valves open when the volt age is applied. The CG then regulates the gas outlet pressure. This pressure fol lows the variable air control pressure. The ratio between gas and air pressure remains constant. At min.-flow operation of the burner, the gas/air mixture can be varied through parallel shifting of the characteristic by adjusting the screw N. High fire is adjust ed with the main flow restrictor. On the CG..V and CG..V3, the combustion cham ber pressure can be compensated for by connection to p F. Working range Permitted gas outlet pressure: = 0.4 to 30 mbar. Permitted air control pressure: = 0.4 to 0 mbar. Zero offset N: CG..G: ±0. mbar CG..V: ±0.4 mbar CG..V3: ±0.6 mbar Gas/air ratios: CG..G: approx. : CG..V: approx. : CG..V3: approx. 3: Permitted combustion chamber pressure: p F = - to + mbar. Minimum control pressure difference: p F = 0.4 mbar. p e p e [mbar] CG 0..G CG 0..V, CG 0..V ,4 V3 V 3 N N +N -N p F G 4 [mbar]

6 CG..E With electronic governor class C, for precise air/gas ratio control for modulating or twostage, sliding draught burners or draughtassisted boilers. Function Both valves open when the voltage is applied. Then the gas outlet pressure is produced via the control current. The flow rate is set via the main flow restrictor. p e Working range Permitted gas outlet pressure: = 0.4 to mbar. Maximum control current: 0 ma. Minimum required control current: epending on installation position 0 to 4 ma. Maximum power consumption:. W. [mbar] E I [ma] 6

7 Selection examples Outlet data: Type of gas: natural gas Min. inlet pressure p e : 8 mbar Max. flow rate V max : m 3 /h Max. outlet pressure : 0 mbar CG.., CG.., CG..E The pressure drop p across the entire combination control can be calculated as follows: p = p e = 8 0 mbar = 8 mbar m 3 /h 8 mbar 8 mbar CG mbar The operating point P (V max. = m 3 /h; p = 8 mbar) must lie in the working range of the combination control CG 0. CG..G, CG..V, CG..V3 Additional outlet data Max. burner air pressure : 4 mbar etermining the transmission ratio U: p U = G = 0 pl =, 4 Select the governor type with the next higher ratio U min.. Governor G U min. =.0 (U max. =.0) Governor V U min. =.9 (U max. =.3) Governor V3 U min.. =.9 (U max. = 3.) The available pressure drop p can be calculated as follows: p = p e U max. * = 8 3, * 4 mbar = 4 mbar The operating point P (V max = m 3 /h; p = 4 mbar) must lie in the working range of the combination control CG 0. m 3 /h 8 mbar 4 mbar CG 0..V3 4 mbar 0 mbar 4 mbar A further 4 mbar must be generated by flow rate adjustment, in addition to the computed pressure drop p = 4 mbar, in order to achieve the required outlet pres sure = 0 mbar. At min. flow, the actual flow rate may not drop below the minimum flow rate V min (see diagram). All GC units If the operating point does not lie in the working range of the CG 0, the inlet vari ables p e, V, or must be adapted. We recommend a different CG control for applications with different capacity de mand. See also CG,, 3, Brochure No Flow rate CG P P = Natural gas, dv = 0.6 = LPG, dv =.6 3 = Air, dv =.00 V' [m 3 /h (n)] 7

8 Accessories Combination control CG 0 can be fitted at the works with a preset pressure switch for gas G..C at the inlet as a low-pressure gas cut-out. Pre-setting: 4 mbar. Electrical connection: coupler plug in accordance with ISO 4400 with cable gland Pg. Flanges N, straight version or angle version available. Both a rectifier adapter for interconnection and a coupler plug with rectifier are avail able for AC voltage. Type code Type CG 0 R * T 6 A W** Z** Size 0 Rp thread Max. inlet pressure p e 70 mbar = 70 Governor = Governor with start gas stage = Air/gas ratio control = G Variable air/gas-ratio control : = V Variable air/gas-ratio control 3: = V3 Electronic governor = E Max. outlet pressure with and : 0 mbar = 0* Mains voltage 0 V= 4 V~ 06 V= 30 V~ = L = H = U = T We reserve the right to make technical modifications in the interests of progress. Elster has an environment-friendly production policy. Please send away for our Environment Report. Rectifier adapter without socket = Rectifier adapter with socket = 6 Without rectifier, without socket = 8 Without rectifier, with socket = 9 Valve class = A, B Pressure switch G 3C = W*, G 4/VC = WV** Special version = Z** * = 40 mbar if "none". ** This letter is omitted if "none". Elster GmbH Postfach Osnabrück Phone ++49 (0) 4/ 4-0 Fax ++49 (0) 4/ info@kromschroeder.com