C7195A2/B/C WATER FLOW SENSOR PRODUCT HANDBOOK APPLICATION The sensor is primarily designed to measure the Domestic Hot Water (DHW) flow rate in domestic appliances as follows: • Combi boiler • Instanteneous Water Heater (IHW) • Other systems such as applications where the instanteneous DHW is produced from district heat input. Subject to change without notice. All rights reserved Contents General Page Description .......................................................................2 Typical applications ..........................................................3 C7195A2, C7195B and C7195C Technical Specifications ...................................................................4 Electrical specifications ....................................................5 Performance .....................................................................6 General considerations ....................................................6 Dimensional drawing ........................................................6 Various Standards and approvals .................................................7 Ordering information ........................................................8 Associated products .........................................................8 1 EN2R-9029 0311R4-NE DESCRIPTION Electronic controller The C7195A2/B/C are mechanical water flow sensors. A wheel (A2 and C type) or a turbine (B type), rotates with water flow. The wheel or the turbine support a magnet which rotates in front of a Hall effect sensor Modulating control Flow rate input for modulation This Hall effect sensor picks up the field of the magnet giving a pulsed output.The output is directly proportional to the water flow through the sensor. This frequency output is easily processed by an electronic controller which can then modulate the burner load (for feedforward loop) or simply open heat demand when the flow reaches its defined minimum rate (electronic flow switch). Cold water The sensor body (the A2 and B type) is constructed from pressure and temperature resistant plastic, with easy connections to traditional pipes used in domestic appliances. The C type (cartridge only) is constructed with the same material, but it is used for integration in customized bodies or water manifold. C7195A2/B/C Heat supply Temperature feedback Option: Compensation of tolerances and hysteresys ˚C Domestic hot water Fig. 1. Feed forward control loop concept Feed forward control loop concept See fig. 1. EN2R-9029 0311R4-NE 2 TYPICAL APPLICATIONS The C7195A2 and B (fig. 3) and the C7195C (fig. 2) Water Flow Sensors are designed to measure the Domestic Hot Water (DHW) flow rate in appliances as follows: • • • Combi boiler (instanteneous or with small buffer) Instanteneous Water Heater (IWH), gas or electric powered. Other systems where DHW is produced instantaneously ˚C ˚C C7195C Temperature feedback ˚C Modulating control Temperature feedback Modulating control Electronic controller Electronic controller Modulation input and/or electronic flow switch Domestic hot water Domestic hot water C7195A2/B Cold water Cold water Fig. 2. Instanteneous combi boiler with feed forward or feed back control loop Fig. 3. Instanteneous water heater with feed forward or feed back control loop o Feedback control loop This is the traditional electronic control, reacting to the DHW temperature sensor output. A flow detector is needed to detect when the DHW is tapped. The C7195 water flow sensor can be used as an electronic flow switch with the following advantages over ON/ OFF switches: • Flexibility: Electronically (auto)adjustable ON-point, for instance depending on DHW temperature setting point (to avoid ON/OFF recycling) • Safety: Can not be blocked in ON position (weel or turbine can only turn with flow). For the above mentioned appliances, the sensor can be used in two specific ways: n Feed forward control loop This is an advanced electronic control concept which improves the DHW temperature control thanks to fast reaction to flow rate changes. Indeed, before the temperature sensor sees a change in hot side, the electronic board can react promptly following the flow measurement. A temperature sensor can be used anyway as an option to compensate the tolerances and hysteresis of the complete system. 3 EN2R-9029 0311R4-NE SPECIFICATIONS Model C7195A/B/C water flow sensor Ambient temperature -20 ... + 85°C Dimensions See fig. 9 for C7195A2 See fig. 10 for C7195B See fig. 11 for C7195C Fluid Water for sanitary use Permissible fluid temperatur 0 ... 80°C Minimum operating flow rate 1.5 liter/minute or lower Maximum operating flow rate 35 liter/minute Mounting position (C7195A2 only) • The shaft of the rotor shall be horizontal or vertical ± 5°. See fig. 4. • Provided the shaft of the rotor is horizontal, most positions are acceptable, but the position as indicated in fig. 5. is not recommended because water will remain in the sensor when the installation is drained (frost risk). >PPS< 1 Fig. 4. Mounting positions C7195A2 Mounting position (C7195B only) • Recommended position for C7195B is vertical (fig. 6), although horizontal is allowed Fig. 5. Not recommended mounting position EN2R-9029 0311R4-NE 4 Measuring range C7195A2: 2 ... 30 liter/min C7195B: 2 ... 35 liter/min C7195C: 2 ... 30 liter/min (valid when recommended interface dimensions are respected, see fig. 11) Nominal output frequency f = Q x 7.0 (Q = flow rate in l/min; f = pulse signal in Hz) with u 60 mm straight pipe on both sides. Accuracy C7195A2: C7195B: C7195C: -30 ... +10% over 2 to 3 l/min -20 ... +10% over 3 to 10 l/min ± 10% over 10 to 30 l/min -30 ... +10% over 2 to 3 l/min -20 ... +10% over 3 to 5 l/min ± 10% over 5 to 35 l/min Fig. 6. Mounting position for C7195B -30 ... +10% over 2 to 3 l/min -20 ... +10% over 3 to 5 l/min ± 10% over 5 to 30 l/min (valid when recommended interface dimensions are respected, see fig. 11) Withstand pressure When a water pressure of 17.5 bar is applied, no external leakage shall be measured and no body damage shall occur. Water connections C7195A2: PF 1/2” minimum 8 mm (4.4 threads) C7195B : PF 3/4” (15 mm quick pipe connection on request) C7195C : Not applicable Recommended tightening torque of inlet/outlet connections 2.5 ... 3.5 Nm Pressure drop 0.15 bar or less at 10 l/min flow rate. (Outlet pressure is at atmospheric pressure) Endurance Indicated value will shift < 5% under following conditions: 10000 hr at 10 l/min and 20°C 7000 hr at 4 l/min and 45°C or 100,000 cycles ON/OFF at 10 l/min and 45°C Housing material PPS Flow limiter Inlet port seat suitable for water flow limiter from NEOPERL® C7195A2: type ‘MR01 FG’ C7195B: type ‘MR04 AKM’ 5 EN2R-9029 0311R4-NE ELECTRICAL SPECIFICATIONS Nominal voltage (Vcc): Current (Isink): 10 mA (absolute maximum: Output saturation voltage (Vsat) : Electrical code (recommended) White: Vout Red: Vcc Black: ground 12 V (absolute maximum: 18 V) 15 mA) Duty cycle of electrical output signal 30 ... 70% Supply current (Icc): < 0.4 V with output “ON” and at Isink = 10 mA 8 mA with output “OFF” Cable: 1 meter cable : 45.900.419-039 Molex 5045-03A V out V cc GND Fig. 7. Electrical connection C7195A2/B/C + Vcc 5 ... 12 V 10 kW Vcc + Vout < 0.4 V Hall IC Gnd GENERAL CONSIDERATIONS Fig. 8. Suggested interface schematic PERFORMANCE When magnetic materials like iron or materials which generates magnetism are close to the flow sensor, operation characteristics may change. In order to avoid the invasion of small particles like sand, iron and rust into the water flow sensor, it is advisable to install a mesh filter. The waterflow to the inlet of the flow sensor should be undisturbed to meet the accuracy specifications. If a device causes significant flow disturbance at the inlet of the device, contact your Honeywell representative. Design life 10,000 hour continious operation at 10 l/minute at 20°C 7,000 hour continious operation at 10 l/minute at 45°C or: 100,000 cycles operation (ON = 5 s/OFF = 5 s) at 10 l/minute at 45°C. After life test accuracy must be within ±5% of measured value at first stage. EN2R-9029 0311R4-NE 6 DIMENSIONAL DRAWING 24.35 G 1/2 " Molex, 5045-03A 61 36.4 >PPS< 1 11 38.5 G 1/2 " Fig. 9. Dimensional drawing C7195A2 G 3/4" (24) 15 H30 75 PPS (5.5) 35 Molex, 5045-03A Fig. 10. Dimensional drawing C7195B R0.5 8 +0.1 0 14.8 +0.2 0 32 ±0.1 R1 R1 R1 3.5 ±0.1 R1 14 24.5 0.1 19.8 ± 0.1 30° 1.25 38 30° 1.5 Molex, 5045-03A 24.35 +0.1 3.1 0-0.1 1.35 +0.14 0 -0.2 30 -0.4 31.4 +0.25 0 30 +0.2 0 25.4 0-0.1 24.5 0.1 Fig. 11. Dimensional drawing cartridge (C7195C) and recommended seat dimensions for customzed body or water manifold 7 EN2R-9029 0311R4-NE STANDARDS AND APPROVALS Other countries in general accept this certification. For more details please contact Standards and Appprovals department, Honeywell Combustion Control Center NL05. Approvals The C7195A water flow sensor series have been approved according the United Kingdom Byelaws and Regulations Certificate N0. 9711081, and can therefore be used in potable water applications. Renewal of the certificate to add C7195B and C is pending. The materials used in these sensors are the same. EN2R-9029 0311R4-NE 8 ORDERING INFORMATION Ordering Specification number C7195A X 9999 Specification number: Water flow sensor 2000 ... 2999 for C7195A 1000 ... 1999 for C7195B/C A : Wheel concept B : Turbine concept C : Wheel concept (cartridge for water manifold integration) Fig. 12. Model number chart C7195A/B/C water flow sensor ASSOCIATED PRODUCTS Electronic controller W4115C series for IWH application W4115B series for Combi boiler application W7073C series for Combi boiler application SK series SM series MCBA series CVBC series (S4965) Temperature sensors T7335 series and SO series (NTC thermistor probes), many options available. 9 EN2R-9029 0311R4-NE Home and Building Control Combustion Control Center Europe Honeywell BV Phileas Foggstraat 7 7821 AJ Emmen The Netherlands Tel.: +31 (-)591 695911 Fax: +31 (-) 591 695200 http://europe.hbc.honeywell.com EN2R-9029 0311R4-NE 10