Analog Hydraulic Diagnostic Instruments for Pressure, Flow, and Temperature

Frequently Asked Questions About Analog Hydraulic Diagnostic Tools

A reliable hydraulic diagnosis considers more than just the system pressure. Flow rate and temperature also provide important information about the actual performance of a hydraulic circuit. Here, we answer frequently asked questions about the analog measurement of pressure, flow, and temperature, as well as the use of the HD_RFIK200-B-6_LR.

• What is an analog hydraulic diagnostic tool?

  An analog hydraulic diagnostic device is a measurement system for directly analyzing key operating parameters of a hydraulic system.

  With the HD_RFIK200-B-6_LR, the following parameters—in particular—can be evaluated simultaneously or within a single test setup:

  • Hydraulic pressure
  • Volume flow
  • Hydraulic oil temperature

  This means the device goes beyond simply measuring pressure with a pressure gauge.

• What parameters does the HD_RFIK200-B-6_LR measure?

  The test device combines three key measurement parameters: In addition, the device features a built-in load valve that allows the operating pressure to be gradually increased during a performance test.

  • Pressure in bar
  • Flow rate in l/min
  • Temperature in °C
• What are the measurement ranges of the analog hydraulic diagnostic tool?

  The HD_RFIK200-B-6_LR is designed for the following applications: This makes the system suitable for numerous applications in mobile hydraulics.

  • Maximum rated pressure: up to 420 bar
  • Flow rate: 10–200 l/min
  • Fluid temperature: 20–80 °C
• How accurately does the analog hydraulic diagnostic tool measure?

  The following display accuracies are specified for the HD_RFIK200-B-6_LR: When evaluating the measurement results, the respective setpoints and test specifications of the machine or hydraulic system must also be taken into account.

  • Pressure: ±1.6%
  • Flow rate: ±4%
  • Temperature: ±2.5 °C
• Why is simply measuring pressure not always sufficient for hydraulic diagnostics?

  Pressure and flow rate describe different characteristics of a hydraulic system.

  For example, a pump can generate high pressure, while the actual flow rate may no longer be sufficient.

  This can lead to symptoms such as:

  • slow cylinder movements
  • low operating speed
  • performance drop under load
  • abnormal behavior of hydraulic motors

  In such cases, additional flow measurement provides important information.

• What does the hydraulic pressure indicate?

  The pressure is generated by the load or flow resistance in the hydraulic system.
  
  It provides information about the pressure present at the respective measuring point under the given operating conditions.
  
  A measured pressure value must always be compared with the system's technical setpoints.

• What does the flow rate indicate?

  The flow rate describes the volume of hydraulic fluid that flows through the system or the flow meter block within a given time.

  It is typically expressed in liters per minute.

  The flow rate affects, for example, the speed of:

  • hydraulic cylinders
  • hydraulic motors
  • lifting functions
  • working movements

  Therefore, sufficient pressure does not automatically mean that the required flow rate is also present.

• Why is the hydraulic oil temperature measured at the same time?

  Among other things, temperature affects the viscosity of the hydraulic oil and, consequently, the system’s operating behavior.
  
  In addition, an unusually high oil temperature may indicate increased power loss or other problems in the system.
  
  Pressure and flow rate values should therefore be considered in conjunction with the operating temperature when performing complex diagnostics.

• What is the relief valve in the HD_RFIK200-B-6_LR?

  The integrated load valve makes it possible to apply a specific hydraulic resistance to the hydraulic system during testing.
  
  This allows the system pressure to be increased gradually while observing how the pressure and flow rate behave under increasing load.
  
  This is useful, for example, for performance testing of a hydraulic pump.

• Why is a hydraulic pump tested under load?

  A hydraulic pump may initially operate without any noticeable issues when under no significant load.

  Only as the hydraulic load increases will it become apparent whether:

  • the required pressure is reached,
  • the necessary flow rate is maintained,
  • the flow rate drops,
  • the system heats up unusually.

  A load test therefore allows for a more realistic assessment than a simple measurement under no-load conditions.

• Can this device be used to evaluate the performance of a hydraulic pump?

  Yes.
  
  By analyzing both pressure and flow rate under defined conditions, it is possible to assess a pump’s hydraulic performance.
  
  However, the test device does not automatically indicate whether the pump is “good” or “defective.”
  
  The measurement results must be compared with the technical specifications provided by the machine or pump manufacturer.

• Can a hydraulic pump reach the correct pressure even if it is worn out?

  Yes.
  
  Under certain conditions, a pump can still reach the specified pressure while delivering an insufficient flow rate.
  
  This is precisely why combined pressure and flow measurement is particularly useful in pump diagnostics.

• Which components can be tested using the analog hydraulic tester?

  The HD_RFIK200-B-6_LR can be used for performance and functional testing of various components and systems.

  These include, for example:

  • Hydraulic pumps
  • Hydraulic motors
  • Valves
  • Steering systems
  • Hydraulic cylinders
  • Complete hydraulic circuits

  The specific measurement method depends on the design and manufacturer’s specifications of the respective system.

• Can a hydraulic cylinder be tested using this device?

  During the inspection of a cylinder circuit, the diagnostic device can provide important information about pressure and flow rate.
  
  This allows for the detection of abnormalities in hydraulic behavior.
  
  Whether a detected fault is actually caused by an internal cylinder leak, a valve, or another component must then be narrowed down using the appropriate test setup.

• Can a hydraulic motor be tested?

  Yes.
  
  In a hydraulic motor, pressure and flow rate can provide important information about its operating behavior.
  
  If the speed is abnormal or the power output is too low, for example, you can check whether the required flow rate and pressure are actually present at the motor.

• Can a hydraulic valve be tested?

  Yes.
  
  Leitenberger specifically mentions steering systems as a potential application for the HD_RFIK200-B-6_LR.
  
  Pressure and flow rate can help determine whether the hydraulic supply is sufficient under the intended operating conditions.

• Where is the hydraulic diagnostic tool connected?

  Depending on the intended test procedure, the test device can be connected to the pressure or return line of the hydraulic system.

  The correct measurement point depends on:

  • Hydraulic schematic
  • the component to be tested
  • flow direction
  • pressure range
  • the machine manufacturer’s specifications.

  Therefore, before connecting the device, it must be clearly established which circuit is to be tested.

• Can the device be used in the pressure line?

  Yes.
  
  The HD_RFIK200-B-6_LR can be integrated into the pressure line in accordance with the specified test setup.
  
  In doing so, the maximum system pressure as well as the permissible pressure ranges of the test device, hose lines, couplings, and adapters must be taken into account.

• Can the device also be installed in the return line?

  Yes.
  
  Depending on the diagnostic task, Leitenberger also provides for a connection to the return line.
  
  A return line measurement can, for example, be helpful in evaluating certain flow rates or system conditions.
  
  The permissible test setup must be compatible with the hydraulic system in question.

• What is the connector size of the tester?

  The HD_RFIK200-B-6_LR has a 1" BSPP connection.
  
  Appropriate hydraulic hoses, couplings, and adapters are required for connecting it to the machine or system.

• Does the analog hydraulic diagnostic tool require power?

  No.
  
  The tester requires neither batteries nor a rechargeable battery nor an external power source.
  
  Pressure, flow, and temperature are displayed on the built-in analog gauges.
  
  This can be particularly useful for mobile service and when working directly on machines.

• What is the advantage of an analog hydraulic diagnostic tool?

  The advantages include, in particular:

  • no electrical power required
  • direct display of measured values
  • robust mechanical design
  • pressure, flow, and temperature measurement in a single system
  • integrated test valve
  • easy to use in mobile service

  For applications where data logging or digital documentation is not required, an analog system can be a very practical solution.

• What is the difference between analog and digital hydraulic diagnostics?

  Both systems can measure key physical parameters of a hydraulic system.

  The analog HD_RFIK200-B-6_LR uses direct analog displays and requires no power.

  Digital hydraulic diagnostic devices for pressure, flow, and temperature, on the other hand, offer additional features such as:

  • digital display
  • automatic sensor detection
  • multiple measurement channels
  • measurement value storage
  • data logging
  • USB transfer
  • subsequent evaluation of measurement data

  Which system is more suitable depends on the diagnostic task and the documentation requirements.

• Can the analog device store measurement values?

  No.

  The HD_RFIK200-B-6_LR does not have an electronic data logger.

  The measured values are read directly from the pressure gauge, flow meter, and thermometer.

  If you need to save measurement data and analyze it later, a digital hydraulic diagnostic device is a better choice.

• Can I use the analog device to record a pressure curve?

  Automatic electronic recording is not possible.
  
  Individual measurement values can, of course, be documented manually.
  
  For longer measurement recordings or subsequent graphical analysis, however, the HD-01 digital system with data logging is suitable.

• Can the analog hydraulic diagnostic tool be calibrated?

  Leitenberger does not currently offer factory calibration for the HD_RFIK200-B-6_LR.

  If a system with a factory calibration certificate is required, Leitenberger recommends, for example, the HD 01_Set_02 digital hydraulic diagnostic device.

• So when should I choose the Digital HD 01?

  The digital system is particularly useful when:

  • a factory calibration certificate is required,
  • measurement values need to be stored,
  • pressure trends need to be documented,
  • multiple measurement channels are required,
  • CSV analysis is desired,
  • or different sensor blocks need to be used flexibly.

  For a robust direct performance test without these additional functions, however, the analog device may be sufficient.

• What is the difference between this and a hydraulic digital pressure gauge?

  A digital hydraulic pressure gauge primarily measures hydraulic pressure.

  The analog hydraulic diagnostic tool also measures flow rate and temperature and is equipped with a load valve for performance testing.

  This makes it better suited for more comprehensive pump and system diagnostics.

• What is the difference between this and an analog hydraulic test kit?

  An analog hydraulic test kit is primarily a portable pressure measurement set consisting of one or more pressure gauges, measuring hoses, and test connections.

  The HD_RFIK200-B-6_LR, on the other hand, is an integrated diagnostic device for:

  • Pressure
  • Flow rate
  • Temperature
  • Load on the hydraulic circuit

  The two product groups therefore serve different diagnostic purposes.

• Why does the device have a steel housing?

  The measuring components are housed together in a sturdy steel enclosure with a removable cover.
  
  This combines the pressure gauge, flow meter, thermometer, and relief valve into a single compact unit.
  
  This is particularly practical for mobile workshop and field use.

• How big is the analog hydraulic diagnostic tool?

  The HD_RFIK200-B-6_LR has approximate dimensions of:

  • 350 mm in length
  • 135 mm in width
  • 140 mm in height

  This makes it a compact, portable test system.

• What is the permissible ambient temperature?

  The specified ambient temperature range for the device is -10 to +50 °C.
  
  The permissible fluid temperature is 20 to 80 °C.
  
  These ranges must be observed during operation.

• Are there any high-pressure hoses that are compatible with this device?

  Yes.

  The HD_Hose Set_4SH_LR is available for the HD_RFIK200-B-6_LR.

  The high-pressure hydraulic hoses comply with DIN EN 856 4SH and feature four steel wire braided reinforcements.

  This provides robust connecting hoses for use with the analog hydraulic tester.

• What types of couplings are used in the hose set?

  The appropriate hose set uses screw couplings from the HS20 series.
  
  These are connected by screwing them together until they stop.
  
  The self-locking threaded connection reduces the risk of accidental loosening due to vibrations.

• Can the couplings be connected under pressure?

  According to the product specifications, the HS screw couplings used in the hose set can be connected under pressure up to a maximum of 50 bar on both sides.
  
  Regardless of this, when working on hydraulic systems, you must always comply with the company’s safety guidelines and follow the prescribed procedures.

• What should be kept in mind when performing high-pressure hydraulic measurements?

  Hydraulic systems can operate at very high pressures.

  Therefore, before each measurement, the following must be checked in particular:

  • the test device’s maximum allowable pressure
  • the pressure resistance of the hoses
  • the condition of the couplings
  • that all connections are properly secured
  • suitable adapters
  • the correct flow direction
  • temperature limits

  Damaged or unsuitable components must not be used.

• Why can hydraulic leaks be dangerous?

  Hydraulic fluid escaping under high pressure can form very fine jets and cause serious injury.
  
  Therefore, do not search for leaks by hand.
  
  Hydraulic measurements should only be performed by appropriately qualified personnel using suitable equipment.

• For which machines is the analog hydraulic diagnostic tool suitable?

  The test device is particularly well-suited for mobile hydraulic applications.

  Typical areas of application include, for example:

  • Agricultural machinery
  • Construction machinery
  • Forestry machinery
  • Municipal machinery
  • Commercial vehicles
  • Other mobile machinery

  The key factors are the available pressure, the flow rate, the connection size, and the specific test task.

• Is this device particularly well-suited for agricultural machinery?

  Yes.

  Leitenberger specifically markets this analog hydraulic tester for agricultural and other mobile machinery.

  Agricultural machinery often features extensive hydraulic systems, where the simultaneous measurement of pressure and flow rate can play an important role in troubleshooting.

  For electronically controlled machines, hydraulic testing can also be combined with the Jaltest Diagnostics for Agricultural Machinery and Vehicles.

• Can the device also be used with construction equipment?

  Generally speaking, yes, provided that the pressure, flow rate, connection, and temperature are within the permissible ranges.

  For construction machinery, the hydraulic measurement can be supplemented, if necessary, by the Jaltest Diagnostics for Construction Machinery and Off-Highway Vehicles.

  This allows electronic diagnostics to be compared with actual hydraulic measurement values.

• Can an electronic diagnosis replace hydraulic measurement?

  Not entirely.

  For example, an electronic diagnostic system can display:

  • error codes
  • sensor signals
  • ECU information
  • actuator statuses.

  The analog hydraulic tester, on the other hand, directly measures:

  • pressure
  • flow rate
  • temperature

  in the hydraulic circuit.

  In cases of complex fault patterns, both methods complement each other.

• For which types of businesses is the analog hydraulic diagnostic tool particularly suitable?

  The device is particularly suitable for:

  • Agricultural machinery repair shops
  • Construction equipment service centers
  • Mobile field service technicians
  • Hydraulic service shops
  • Forestry and municipal equipment
  • Commercial vehicle repair shops
  • Machinery maintenance

  It is particularly useful in applications where robust pressure, flow, and temperature measurements are required directly on the machine, but electronic data logging is not necessary.

  You can find additional test and measurement systems under Test and Diagnostic Equipment for Hydraulic Systems.