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Maintenance Indicators

Filtration Group

973-948-0226
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Spec/Diagram PDF

Item Information:

Filter elements are economically used only if their dirt holding capacity is fully exploited. This is achieved by using filter housings with a maintenance indicator. Filtration Group manufactures maintenance indicators of the following designs:

  • Differential pressure indicators
  • Pressure indicators/switches/gauges
  • Vacuum switches/gauges

Features

With any filter element the collection of dirt particles continously reduces the number of open pores or, in other words: The open cross section for allowing the liquid to flow is continously reduced. Thus the pressure on the upstream side of the element (dirt side) increases continously.

With pressure filters, the pressure is measured upstream and downstream of the filter element (differential pressure). With return line filters the pressure is measured only on the upstream side because, depending on the tank design, atmospheric pressure exits on the downstream side of the filter element is measured analog. With suction filters the vacuum is measured downstream.

A piston with attached magnet is moved against the force of a spring, with which the indicating point is determined by the piston surface. A homopolar poled magnet is fitted in the outer part in the indicating button.

The closer the pole-springs move towards each other, the stronger is the force with the magnets mutually repel, until finally the red button on the indicator pops out.

This red button remains visible until it is pushed in during the daily check which is to be performed while the plant is at operating temperature. If the button pops out immediately after being pushed in, the filter element must be replaced latest at the end of the shift.

This optical function may also be used for generating contactless electrical signals. For this purpose an electrical upper part is pushed over the hydraulic/optical part. This upper part incorporates all electrical switching elements.

  • Differential pressure indicators
  • Pressure indicators/switches/gauges
  • Vacuum switches/gauges
  • Optical and electrical indicator with standard check function
  • Normally open/normally closed combination - standard feature
  • Electrical function, easy to install at a later time
  • Two-step indication, at 75 % and 100 % optional
  • Signal lock out up to approx. 30 °C optional
  • Rugged, non-bypass design
  • Optimal element exploitation
  • Worldwide distribution

 

  2. Differential Pressure Indicators


*Contact type
1    Normally open/normally closed; 1 setting point; wiring box DIN EN 175301-803; max. 250 V AC/200 V DC; max. 1 A
2   Normally closed; 2 setting points; wiring box DIN EN 175301-803; max. 150 V; max. 1 A
3   Change-over contact; 1 setting point; wiring box DIN EN 175301-803; max. 150 V; max. 1 A
4   Change-over contact; 2 setting points; LED; Mercedes Benz Norm DBL 9666 EA; wiring box DIN EN 175201-804; max. 10-30 V; max. 1 A
5   Change-over contact; 2 setting points; LED; signal surpression; time delay; wiring box DIN EN 175201-804; 10-30 V; max. 1 A
6   Change-over contact; 2 setting points; LED; signal surpression; wiring box DIN EN 175201-804, 10-30 V; max. 1 A
7   Analog signal 4-20 mA; 2 setting points; LED; signal cold start; wiring box DIN EN 175201-804; 24 V; max. 1 A
8   Normally open/normally closed; 2 setting points; LED; signal surpression; plug connection M12x1; 10-30 V; max. 1 A
9   Normally open/normally closed; 2 setting points; LED; plug connection M12x1; 10-30 V; max. 1 A
10   Change-over contact;1 setting point; plug connection M12x1; 150 V; max. 1 A
11   Normally closed/normally closed; 2 setting points; LED; plug connection M12x1; 150 V; max. 1 A

3. Pressure Indicators/Pressure Switches4. Vacuum/Pressure Gauges5. Vacuum Switches6. Vacuum Indicators/Air Filters7. Accessories

8. Function

The magnetic field as previously described, contactless operates reed contacts in the electrical upper part. The desired contact type is selected by inverting upper part. Another option keeping the electrical signal electronically suppressed up to 30 °C operating temperature is also available. This eliminates false electrical signal during the cold start phase. For efficient servicing it is desirable to have a pre-warning device (so that the filter element can be replaced, e.g. with the next tool change). For this purpose electrical upper parts with two indicating points, i.e. at 75 % and at 100 % of the indicator setting are available.Pressure/vacuum gauges give an analog reading of the existing state of contamination of the filter elements. They require continous control to ensure that the service time and reserve capacity are not unduly exceeded. If the contamination signal is disregarded, the filter element may collapse or, if a bypass valve is installed, part of the contamination fluid may reach the hydraulic components via the bypass valve and cause failure of the hydraulics. Pressure/vacuum switches are provided with snap action switches, which ascertains that signal are issued only when the limit values have been fully reached.9. Technical specifications

9.1 Contact type normally open/normally closed
Contact type 1  
Types PiS 3085, 3086, 3092, 3097, 3192  
Maximum voltage: 250 V AC/200 V DC
Maximum current: 1 A
Contact load: 70 W
Type of protection: IP 65 in inserted and
  secured status
Contact type: normally open/normally closed
Cable sleave: M20x1.5
Wiring box: DIN EN 175 301-803
The switching function can be changed by turning the electric upper part by 180° (normally closed contact or normally open contact). The state on delivery is a normally closed contact. By inductivity in the direct current circuit the use of suitable protection circuit should be considered. Electrical parts are insulated (plastic material housing).
9.2 Contact type normally closed or open with signal suppression
Contact type normally closed
Type PiS 3003 (expansion kit)
Contact type normally open
Type PiS 3002 (expansion kit)

Signal suppression by thermorelay

Signal is released at +30 °C

for further technical details see 9.1

9.3 Contact type normally closed 2 setting points
Contact type 2  
Types PiS 3105, 3106, 3119  
1. setting point at 75 % of the indicating pressure
2. setting point at 100 % of the indicating pressure
Max. voltage: 150 V AC/DC
Max. current: 1 A
Contact load: 20 VA/20W
for further technical details see 9.1
9.4 Contact type Change-over contact
Contact type 3
Types PiS 3115, 3116, 3125
Max. voltage: 150 V AC/DC
Max. current: 1 A
Contact load: 20 VA/20W
for further technical details see 9.1

9.5 Contact type change-over contact, 2 setting points LED
Contact type 4  
Types PiS 3012, 3102, 3103, 3104  
1. setting point at 75 % of the indicating pressure
2. setting point at 100 % of the indicating pressure
Max. voltage: 10 - 30 V DC
Max. current: 1 A
Contact load: 20 VA/20W
Type of protection: IP 65 in inserted and
  secured status
Plug connection: DIN EN 175201-804
9.6 Wiring box with insert lamp

Will be suplied instead of standard connection.

Not to be combined with indicators with 2 setting points.

Max. voltage: 12-230 V AC/DC

9.7 Contact type change-over contact, 2 setting points, LED, signal suppression, time delay
Contact type 5  
Types PiS 3131, 3132, 3133  
1. setting point at 75 % of the indicating pressure
2. setting point at 100 % of the indicating pressure
Max. voltage: 10 - 30 V DC
Max. current: 1 A
Contact load: 20W
Type of protection: IP 65 in inserted and
  secured status
Plug connection: DIN EN 175201-804
Signal suppression: by thermorelay
Signal released: at + 30 °C
Signal change down: at + 20 °C
Impulse surpression K1 and K2 time delay 10 s
9.8 Contact type change-over contact, 2 setting points, LED, signal suppression
Contact type 6  
Types PiS 3141, 3142, 3143  
1. setting point at 75 % of the indicating pressure
2. setting point at 100 % of the indicating pressure
Max. voltage: 10 - 30 V DC
Max. current: 1 A
Contact load: 20W
Type of protection: IP 65 in inserted and
  secured status
Plug connection: DIN EN 175201-804
Signal suppression: by thermorelay
Signal released: at + 30 °C
Signal change down: at + 20 °C

9.9 Contact type analog 4-20 mA, 2 setting points, LED, signal suppression
Contact type 7  
Types PiS 3110, 3120  
 
 
Max. voltage: 24 V DC
Max. current:  
Contact load:  
Type of protection: IP 65 in inserted and
  secured status
Plug connection: nach DIN EN 175201-804
Output signal: 4-20 mA
Outputs (PNP, max. 200 mA): cold start signal
  75 % setting point
  100 % setting point
Signal damping: 20 s
9.10 Contact type normally open/normally closed, 2 setting points, LED, signal suppression
Contact type 8  
Types PiS 3151, 3152, 3153  
1. setting point at 75 % of the indicating pressure (normally open)
2. setting point at 100 % of the indicating pressure (normally closed)
Max. voltage:  
Max. current:  
Contact load:  
Type of protection: IP 65 in inserted and
  secured status
Plug connection: M12x1, 4 pole
Signal suppression: by thermorelay
   
Signal released: at + 30 °C
Signal change down: at + 20 °C

9.11 Contact type normally open/normally closed, 2 setting points
Contact type 9  
PiS 3154, 3155, 3156  
1. setting point at 75 % of the indicating pressure (normally open)
2. setting point at 100 % of the indicating pressure (normally closed)
Max. voltage: 10-30 V DC
Max. current: 1 A
Contact load: 20 W
Type of protection: IP 65 in inserted and
  secured status
Plug connection: M12x1, 4 pole
9.12 Contact type change-over contact
Contact type 10  
PiS 3115-M12x1, 3116-M12x1, 3125-M12x1  
 
 
Max. voltage: 150 V
Max. current: 1 A
Contact load: 20 W
Type of protection: IP 65 in inserted and
  secured status
Plug connection: M12x1, 4 pole

9.13 Contact type normally closed, 2 setting points
Contact type 11  
Types PiS 3157, 3158, 3159  
1. setting point at 75 % of the indicating pressure (normally open)
2. setting point at 100 % of the indicating pressure (normally closed)
Max. voltage: 10-30 V DC
Max. current: 1 A
Contact load: 20 W
Type of protection: IP 65 in inserted and
  secured status
Plug connection: M12x1, 4 pole
9.14 Vacuum switch HES/LES
Contact type normally open  
   
Electrical connection: AMP 6,3 DIN 43248
 
  bushings DIN 46247
  switch type 2 pole
Contact load HES*: 42 V/6 W
Contact load LES*: 24 V/6 W
Type of protection: IP 54 - with protecting cap
   
  * at resistive load

9.15 Vacuum switch HEO/LEO
Contact type normally closed  
Contact load HEO*: 42 V/6 W
Contact load LEO*: 24 V/6 W
  * at resistive load
for further technical details see 9.8  
9.16 Vacuum switch PiS 3070
Contact type 1 pole change-over contact  
Electrical connection: AMP 6,3 DIN 43248
  bushings DIN 46247
Max. voltage: 230 V AC/DC
Max. current: 6 A
Type of protection: IP 00 without cover
  IP 54 with cover
Position of installation: individual (position of installation
  is to be adviced if setting pont is adjusted)

9.17 Pressure switch DSS
Contact type normally open
Electrical connection: AMP 6,3 DIN 46248
  bushings DIN 46247
  switch type 2 pole
Max. voltage: 42 V
Max. current: 2 A
Contact load: 100 VA
Duty classification: 200/min
9.18 Pressure switch DSO
Contact type normally closed
for further technical details see 9.17  

Maintenance indicators PiS 3084, 3087, 3093, 3098, 3193 can be mounted in 45°.

We draw attention to the fact that all values indicated are averagevalues which do not always occur in specific cases of application: Our products are continually being further developed. Values, dimensions and weights can change as a result of this. Our specialized departement will be pleased to offer you advice.

When using our filters in areas which are to be classified according to EU directive 94/9 EG (ATEX), we recommend prior discussion with us. The standard version can be used for liquids based on mineral oil /corresponding to the fluids in Group 2 of Directive 97/23 EG Articlel 9). Please consult with us if using other media.

Subject to technical alterations without prior notice.

NAHAD
FPDA 50 Years