Honeywell ZF DATASHEET

Pressure switches

Mechanical pressure switches

Technical features / Advantages

Wall mounting

or directly on the pressure line

Switching element (microswitch)

Lead sealable setpoint adjustment

Setting spindle locking element

Terminal connection or plug connection to DIN 43 650 Form A

Stainless steel sensor housing

Stainless steel bellows

with internal stop

Pressure connection

G 1/2“ external G 1/4” internal

Centring pin

Diecast aluminium housing IP 54 or IP 65

version also available

Pressure switches

Mechanical pressure switches

Pressure switches

General description

Operating mode

The pressure occurring in the sensor housing (1) acts on the measuring bellows (2). Changes in pressure lead to movements of the measuring bellows (2) which are transmitted via a thrust pin (4) to the connecting bridge (5). The connecting bridge is frictionlessly mounted on hardened points (6). When the pressure rises the connecting bridge (5) moves upwards and operates the microswitch (7). A counterforce is provided by the spring (8) whose pretension can be modified by the adjusting screw (9) (switching point adjustment). Turning the setting spindle (9) moves the running nut (10) and modifies the pretension of the spring (8). The screw (11) is used to calibrate the microswitch in the factory. The counter-pressure spring (12) ensures stable switching behaviour, even at low setting values.

Pressure sensors

Apart from a few exceptions in the low-pressure range, all pressure sensors have measuring bellows, some made of copper alloy, but the majority of high-quality stainless steel. Measured on the basis of permitted values, the measuring bellows are exposed to a minimal load and perform only a small lifting movement. This results in a long service life with little switching point drift and high operating reliability. Furthermore, the stroke of the bellows is limited by an internal stop so that the forces resulting from the overpressure cannot be transmitted to the switching device. The parts of the sensor in contact with the medium are welded together without filler metals. The sensors contain no seals. Copper bellows, which are used only for low pressure ranges, are soldered to the sensor housing. The sensor housing and all parts of the sensor in contact with the medium can also be made entirely from stainless steel 1.4571 (DNS series). Precise material data can be found in the individual data sheets.

Pressure connection

The pressure connection on all pressure switches is executed in accordance with DIN 16288 (pressure gauge connection G 1/2A). If desired, the connection can also be made with a G 1/4 internal thread according to ISO 228 Part 1. Maximum screw-in depth on the G 1/4 internal thread = 9 mm.

Centring pin

In the case of connection to the G 1/2 external thread with seal in the thread (i.e. without the usual sheet gasket on the pressure gauge connection), the accompanying centring pin is not needed. Differential pressure switches have 2 pressure connections (max. and min.) each of which are connected to a G 1/4 internal thread.

1 = Pressure connection 2 = Measuring bellows 3 = Sensor housing 4 = Thrust pin 5 = Connecting bridge 6 = Pivot points 7 = Microswitch or other switch-

ing elements

8 = Setting spring 9 = Setting spindle (switching

point adjustment)

10 = Running nut (switching point

indicator)

11 = Microswitch calibration

screw (factory calibration)

12 = Counter pressure spring

General technical data

Diecast aluminium GD AI Si 12 Diecast aluminium GD AI Si 12 G 1/2 external thread (pressure gauge connection) and G 1/4 internal thread G 1/4 internal thread for DDCM differential pressure switches Floating changeover contact. Floating changeover contact. With rising pressure switching With rising pressure switching single-pole from 3-1 to 3-2. single-pole from 3-1 to 3-2.

8 A at 250 VAC 3 A at 250 VAC 5 A at 250 VAC inductive 2 A at 250 VAC inductive 8 A at 24 VDC 3 A at 24 VDC

0.3 A at 250 VDC 0.03 A at 250 VDC min. 10 mA, 12 VDC min. 2 mA, 24 V DC preferably vertical vertical (see technical data sheet)

IP 54; (for terminal connection …300 IP 65) IP 65 – EEx de IIC T6 tested to EN

50014/50018/50019 (CENELEC) – PTB 02 ATEX 1121 Plug connection to DIN 43 650 (200 series) Terminal connection or terminal connection (300 series) PG 11 / for terminal connection M 16 x 1.5 M 16 x 1.5 See data sheets –15 to +60°C Adjustable via spindle. On switching device Adjustable via spindle after the 300 the terminal box cover must be removed terminal box lid is removed

Adjustable or not adjustable Not adjustable (see Product Summary) Only possible on plug connection housing 200 Max. 70°C, briefly 85°C Max. 60°C Higher medium temperatures are possible provided the above limits for the switching device are ensured by suitable measures (e.g. siphon). All pressure switches can operate under vacuum. This will not damage the device.

< 1% of the working range (for pressure ranges > 1 bar)

No significant deviations up to 4 g. With sinusoidal pressure application and room temperature, 10 x 106 switching cycles. The expected life depends to a very large extent on the type of pressure application, therefore this figure can serve only as a rough estimate. With pulsating pressure or pressure impacts in hydraulic systems, pressure surge reduction is recommended. Overvoltage category III, contamination class 3, reference surge voltage 4000 V. Conformity to DIN VDE 0110 (01.89) is confirmed. The parts of all pressure switches with sensors made from steel or stainless steel are oil and greasefree. The sensors are hermetically encapsulated. They contain no seals. (See also additional function ZF 1979 Special Packing)

Switch housing Pressure connection

Switching function and connection diagram

(applies only to version with microswitch)

Switching capacity

(applies only to version with microswitch)

Mounting position

Degree of protection (in vertical

position)

Ex degree of protection

PTB approval Electrical connection

Cable entry Ambient temperature Switching point

Switching differential

Lead seal Medium temperature

Vacuum

Repetition accuracy of switching points Vibration strength Mechanical life

Isolation values

Oil and grease-free

Normal version

Plug connection Terminal connection

…200 …300

version

…700

with microswitches of the DCM, VCM, DNM, DNS and DDC series.

The technical data of type-tested units may differ slightly. (please refer to type sheet)

Pressure switches

Mechanical pressure switches

Pressure switches

Mechanical pressure switches

ZF additional functions — Pressure switches and pressure monitors

Example for ordering: DWR 6 – 205

Code of additional function (e.g. maximum limiter) Code for pressure range Sensor system

How to order:

Pressure switch DWR 6–205 or DWR 6 with ZF 205

…301

ZF 203

ZF 205 see

DWR series

ZF 206 see

DWR series

ZF 307 *

ZF 217 *

ZF 213

Normal version (plug connection)

Microswitch, single pole switching Switching differential not adjustable

Terminal connection – housing (300)

Unit with adjustable switching differential

Maximum limiter

with reclosing lockout

Interlocking with rising pressure

Minimum limiter

with reclosing lockout

Interlocking with falling pressure

Two microswitches, switching in parallel or in

succession. Fixed switching interval, only possible with terminal connection housing. State the switching interval (not possible with all pressure switches, see data sheet p. 2, pp. 40 - 43)

Two microswitches, 1 plug switching in succession. adjustable switching interval

Please indicate switching scheme*

(not possible with all pressure switches, see data sheet p. 2, pp. 40 – 43)

Gold-plated contacts,

single pole switching (not available with adjustable switching differential).

Switch housing with surface protection ZF 351

(chemical version).

Additional functions / Connection diagrams

Plug connection Terminal connection Connection diagram Explanation 200 series (IP 54) 300 series (IP 65)

Permitted contact load: Max: 24 VDC,100 mA Min: 5 VDC, 2 mA

*Switching point adjustment: Please specify switching point and direction of action (rising or falling pressure).

· Housing (300) with terminal connection (IP 65), “blue” cable

entry and terminals.

· Also available with resistor combination for line break and

short-circuit monitoring (with isolating amplifier Ex 041).

Important:

All pressure switches with the ZF 5… additional functions listed here can only be operated in combination with a suitable isolating amplifier (see pages 60 – 61).

Additional functions for EEx-i equipment ZF 5…

DWAM…-576

Pressure switches

Mechanical pressure switches

Additional functions for EEx-i equipment Connection diagram Isolating amplifier

Gold-plated contacts, single-pole ZF 513 Ex 011

switching. Switching differential fixed (not adjustable). Switching capacity: max. 24 VDC, 100 mA, min. 5 VDC, 2 mA.

Versions with resistor combination for line break and short-circuit monitoring in control current circuit, see DBS series, pages 54 – 56:

Normally closed contact with resistor combination ZF 576 Ex 041 for maximum pressure monitoring, gold-plated contacts, plastic-coated housing (chemical version). Normally closed contact with reclosing lockout ZF 577 Ex 041 and resistor combination, for maximum pressure monitoring Plastic-coated housing (chemical version). Normally closed contact with resistor combination ZF 574 Ex 041 for minimum pressure monitoring, gold-plated contacts, plastic-coated housing (chemical version). Normally closed contact with reclosing lockout ZF 575 Ex 041 and resistor combination, for minimum pressure monitoring Plastic-coated housing (chemical version).

Other additional functions Plug connection Terminal connection

200 series 300 series

Adjustment according to customer’s instruction: one switching point ZF 1970* ZF 1970* two switching points or defined switching differential ZF 1972* ZF 1972*

Adjustment and lead sealing according to customer’s instruction: one switching point ZF 1971* – two switching points or defined switching differential ZF 1973* – Labelling of units according to customer’s instruction with sticker ZF 1978 ZF 1978 Special packing for oil and grease-free storage ZF 1979 ZF 1979

Documents: Additional documents, e.g. data sheets, operating instructions, TÜV, DVGW or PTB certificates.

Test certificates according to EN 10 204

Factory certificate 2.2 based on non-specific specimen test WZ 2.2 WZ 2.2 Acceptance test certificate 3.1 based on specific test AZ 3.1 AZ 3.1 Acceptance test certificate for ZFV separating diaphragms AZ 3.1 –V AZ 3.1 –V

*Switching point adjustment: Please specify switching point and direction of action (rising or falling pressure).

Non-Ex area Ex area

For ZF513, ZF576, ZF574: Ui= 15 V DC, Ii= 60 mA, P

= 0.9 W, Ci< 1 nF, Li< 100 µH

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