VARIMETER IMD RN 5897/300 Insulation Monitor

Your Advantages

• For mobile generator sets according to DIN VDE 0100-551
• Preventive fire and system protection
• Detection of symmetric and asymmetric insulation faults
• Universal application in non-earthed AC, DC, AC/DC networks up to max. 300 V
• Easy adjustment of response values and setting parameter via rotational switch
• Suitable for large leakage capacitances up to 30 µF
• Monitoring also with voltage-free mains
• Measuring circuit L(+)/L(-) with broken wire detection (can be switched off)
• Protective conductor PE1/PE2 with broken wire detection (can't be switched off)
• No additional coupling device required

Product Description

The insulation monitor RN 5897/300 of the VARIMETER IMD family provides best and up to date insulation monitoring of modern IT systems in an optimum and state of the art way fulfilling the relevant standards. The device can be used in the most flexible way for AC, DC and AC/DC systems. The adjustment of the setting values is simple and user friendly done on 3 rotary switches on the front of the device. Via multicolor LED the device status is indicated easy to read. With a sealable transparent cover the device is protected against manipulation.

Features

• Insulation monitoring according to IEC/EN 61557-8
• 2 separate adjustable response thresholds (using e.g. for Pre-Alarm and Alarm)
• Setting range of 1st response value (Pre-Alarm): 20 kΩ ... 1 MΩ
• Setting range of 2nd response value (Alarm): 10 kΩ ... 250 kΩ
• 2 changeover contacts for insulation failures - Pre-Alarm and - Alarm
• Energized or de-energized on trip can be selected for indicator relay
• LED for status indication
• Automatic and manual device self-test
• Alarm storage selectable
• Protection against manipulation by sealable transparent cover
• External control input for combined Test-/Reset-button
• 3 wide voltage input for auxiliary voltage
• Width 52.5 mm

Circuit Diagram

The circuit diagram shows connections for L(+), L(-), UH, A1(+), A2, PE1, PE2, and terminal blocks X1, X2, 11, 12, 14, 21, 22, 24. L(+) and L(-) are inputs for the measuring circuit. A1(+) and A2 are for auxiliary voltage. PE1 and PE2 are for the protective conductor. X1 and X2 are for the external control input. Terminals 11, 12, 14 are for Alarm relay K1, and 21, 22, 24 are for Prewarning signal relay K2.

Approvals and Markings

[CE Mark] [cULus Listed Mark] Canada / USA [AC/DC Mark]

Applications

Insulation monitoring of:

• Non-earthed AC, DC, AC/DC networks
• UPS systems
• Networks with frequency inverters
• Battery networks
• Networks with direct current drives
• Hybrid and battery-powered vehicles
• Mobile generator sets

Connection Terminals

Function

Measuring circuit (Insulation measurement between terminals L(+)/L(-) and PE1/PE2)

The device is supplied with DC auxiliary voltage via terminals A1(+) / A2. Switching on the auxiliary voltage (Power-On) is followed by an internal self-test for 12 sec. The test process is visible in the status LED. After this, measurement of the insulation resistance in the measuring circuits begins and the status LED changes to green. The terminals L(+) and L(-) are connected directly to the voltage system to be monitored. A broken wire detection creates a fault signal if there is no low-ohmic connection between both terminals. The type of network (AC, DC, 3NAC) must be selected. Terminals PE1 and PE2 must be connected with 2 separate wires to the protective earth. An interruption of a wire also causes a fault signal. The monitoring of the PE connection cannot be de-activated. To measure the insulation resistance, an active measuring voltage with changing polarity is connected between L(+)/L(-) and PE1/PE2. At the end of a measuring cycle, the actual insulation resistance is produced and indicated. The relays for alarm K1 and pre-alarm K2 switch when dropping under the adjusted response values. The LED changes to orange color on pre-alarm or to red color on alarm.

Manual reset of fault message

The rotary switch "UN" has 2 sections for selecting manual or auto reset. If manual reset is activated, insulation fault signals are stored even if the resistance returns to a healthy state. Pressing the "Reset" button for 2 s resets the alarm signal if the insulation resistance is healthy.

Indicator relay for insulation fault signal

For indicator relays K1 (contacts 11-12-14 for alarm) and K2 (contacts 21-22-24 for pre-alarm), the function (energized on trip or de-energized on trip) can be set via the pre-alarm rotational switch "RA" when the insulation resistance drops below the adjusted response value.

Broken wire detection

The measuring circuits L(+)/L(-) and protective conductors PE1/PE2 are constantly monitored for wire breaks. Broken wire detection between L(+) and L(-) uses a coupled alternating voltage. If this voltage is short-circuited by a low-ohmic connection, the device detects a proper connection. Large capacitances between L(+) and L(-) can cause false readings and should be avoided. Broken wire detection on L(+)/L(-) can be de-activated using rotary switch "RA". Monitoring of PE1/PE2 cannot be de-activated.

Device test functions

Two test functions are implemented: "Self-test" and "Expanded test".

• Self-test: Performed automatically after Power-On and every full operating hour, or manually by pressing the "Test" button for 2 sec. Indicator relays are not affected. Indicated by LED with orange flash code 1. Consists of a negative test phase (approx. 5s) and a positive test phase (approx. 5s) to check internal circuits.
• Expanded test: Initiated by pressing the "Test" button again for 2 sec during the self-test. The sequence is similar to the self-test, but output relays go into alarm state. Indicated by LED with orange flash code 2. Test phases repeat continuously. Can be finished by pressing the "Reset" button for 2 sec.

Test Signal Timing:

• Test signal: Button Test > 2 s or X1/X2 < 3 s
• Reset signal: Button Reset > 2 s or X1/X2 > 3 s

Diagram Description: The diagram shows the measuring voltage (positive and negative phases) over time during self-test (approx. 12s duration) and continuous extended test (approx. 10s duration). It also indicates the relay state (Alarm/No Alarm) and the test signals.

Function

Behaviour with internal device faults

If internal device faults are detected during the test function, the LED flashes continuously red. Indicator relays K1 and K2 switch to the alarm state.

Behavior on faulty connection

Broken wire on L(+)/L(-): Measurement is disabled. Relays K1 and K2 go into alarm state, LED shows red flash code 1. Fault resets automatically after interruption is removed (max. 2 min reaction time). Stored alarm values remain.

Broken wire on PE1/PE2: Causes the same reaction as interrupting the measuring circuit, but the LED indicates red flash code 2.

External control input

Terminals X1/X2 can be connected to an external combined Test-/Reset button. Bridging X1/X2 for approx. 1 s starts the test mode. Bridging for > 3 s resets a stored alarm.

Programming/setting of parameters/set-up of the insulation monitor

All settings are done with 3 rotary switches behind a sealable transparent cover.

• Rotary switch "R": Sets the response value for alarm. The first section enables broken wire detection; the second section disables it.
• Rotary switch "RA": Sets the response value for pre-alarm. The first section sets relay output to de-energized on trip; the second section sets it to energized on trip.
• Rotary switch "UN": Selects the type of network connection. The first section sets auto reset; the second section sets manual reset.

New settings are accepted without device restart.

Function Diagram

The diagram illustrates the hysteresis function for the alarm (K1) and pre-alarm (K2) relays, showing states like "Open circuit operation" and "De-energized on trip" for different configurations (e.g., energized on trip, de-energized on trip, manual reset).

Flashing Codes Status LED

LED-colour: Red

• Flash code 1: Connection failure measuring circuit L(+)/L(-)
• Flash code 2: Connection failure protective conductor PE1/PE2
• Continuously flashing: Internal system error

LED-colour: Orange

• Flashing (code 1): Self test (measuring circuit, measuring voltage, internal tests)
• Flashing (code 2): Extended Test (additional control of indicator relays)

Indicators

The operational status of the device is indicated on a 3-colour LED:

• Off: No auxiliary voltage connected
• Green: Normal operation (Insulation resistance in healthy state)
• Red: Alarm (measured value below alarm response value)
• Orange: Warning (measured value below pre-alarm response value)
• Orange flashing: Test mode procedure
• Red flashing: Failure code

Error Indication

Notes

WARNING Risk of electrocution! Danger to life or risk of serious injuries.

• Disconnect the system and device from the power supply and ensure they remain disconnected during electrical installation.
• The terminals of the control input X1/X2 have no galvanic separation to the measuring circuit L(+) and L(-) and are electrically connected together, therefore they have to be controlled by volt free contacts or bridge. These contacts or bridges must provide a sufficient separation depending on the mains voltage on L(+)-L(-).
• Please do not connect external voltage to terminals X1/X2. The control must only be made by bridging X1 and X2.

! Attention!

• Before checking insulation and voltage, disconnect the monitoring device RN 5897 from the power source!
• In one voltage system only one insulation monitor can be used. This has to be observed when interconnecting two separate systems.
• Device terminals PE1 and PE2 must always be connected via separate lines to different terminal points of the protective-conductor system.
• The device must not be operated without PE1/PE2 connection!

Info Attention!

• The main measuring circuit can be connected with its terminals L(+) and L(-) both to the DC and also AC side of a mixed network. This is done most practically where the primary incoming power supply takes place (e.g., battery networks with connected inverters on the DC side, with Generators/Transformers with connected Rectifiers or inverters on the AC-side). To monitor a 3NAC system, the device can be connected single pole (L(+) and L(-) are bridged, to the neutral of the 3p4w system). The 3 phases have a low-ohmic (approx. 3 - 5 Ohm) connection via the transformer windings, so also insulation failures of the not directly connected phases are detected. Via the rotational switch "UN", the correct type of network needs to be selected.
• If a monitored AC system includes galvanically connected DC circuits (e.g., via a rectifier), an insulation failure on the DC side can only be detected correctly when a current of min 10 mA can flow via the semiconductor connections.
• If a monitored DC system includes galvanically connected AC circuits (e.g., via an inverter), an insulation failure on the AC side can only be detected correctly when a current of min 10 mA can flow via the semiconductor connections.

Technical Data

Measuring circuit L(+) / L(-) to PE1 / PE2

• Nominal voltage U: AC/DC 0 ... 230 V
• Max. voltage range U: AC/DC 0 ... 300 V
• Frequency range: DC or 40 ... 1000 Hz
• Max. line capacitance: 30 µF
• Internal resistance (AC / DC): > 120 kΩ
• Measuring voltage: Approx. ± 90 V
• Max. measured current (R=0): < 0.80 mA
• Response inaccuracy: ±15% ± 1.5 kΩ (IEC 61557-8)
• Response value hysteresis: Approx. + 25%; min. + 1 kΩ
• On delay at C=1µF, R of ∞ to 0.5* response value: ≤ 1 s (at setting 3N AC)
• Measuring time: < 5 s (at setting AC, DC)
• Response values: Pre-warning ("RPA"): kΩ: 20 50 100 500 1000
• Alarm ("RA"): kΩ: 10 20 50 100 250
• Each adjustable via rotational switches
• Response value broken wire detection L(+)/L(-): > Approx. 30 kΩ
• Response value broken wire detection PE1/PE2: > Approx. 0.5 kΩ

Auxiliary voltage input A1(+)/A2

*) W = Permitted residual ripple of auxiliary supply

Nominal consumption:

• DC 24 V, 48 V: Max. 3 W
• AC 230 V: Max. 3.5 VA

Control input X1/X2 for external kombinierte Test-/Reset-Taste

• Current flow: Approx. 3 mA
• No-load operation voltage X1 to X2: Approx. 12 V
• Permissible wire length: < 50 m
• Activation time for test signal: Approx. 1 s
• Activation time for reset signal: > 3 s

Outputs

• Indicator contact: 2 x 1 changeover contact for Alarm (K1) and Pre-Alarm (K2) energized or de-energized on trip (programmable)
• Thermal current Ith: Max. 4 A
• Switching capacity to AC 15: 5 A / AC 230 V (NO contact)
  2 A / AC 230 V (NC contact)
• To DC 13: 2 A / DC 24 V
• Electrical life at 5 A, AC 230 V: 1 x 10⁵ switching cycles (IEC/EN 60947-5-1)
• Short circuit strength max. fuse rating: 4 A gG/gL
• Mechanical life: 50 x 10⁶ switching cycles (IEC/EN 60947-5-1)

General Data

• Operating mode: Continuous operation
• Temperature range Operation: -40 ... +70 °C
• Auxiliary voltage DC 12 ... 24 V, AC/DC 24 ... 60 V: -40 ... +60 °C
• Auxiliary voltage AC/DC 85 ... 230 V: -40 ... +70 °C (device mounted with min. 1 cm distance to adjacent devices or device with max. 2 x 0.5 A contact current)
• Storage: -40 ... +70 °C
• Altitude: < 2000 m (IEC 60664-1)

Clearance and creepage distances

• Rated insulation voltage: 300 V
• Overvoltage category: III
• Rated impulse voltage / pollution degree: See table below (IEC 60664-1)

• Insulation test voltage Routine test: AC 2.5 kV; 1 s

EMC

• Electrostatic discharge (ESD): 8 kV (air) (IEC/EN 61000-4-2)
• HF irradiation: 80 MHz ... 1 GHz: 20 V/m (IEC/EN 61000-4-3)
  1 GHz ... 2.7 GHz: 10 V/m (IEC/EN 61000-4-3)
• Fast transients: 2 kV (IEC/EN 61000-4-4)
• Surge voltage: Between wires for power supply: 1 kV (IEC/EN 61000-4-5)
  Between wire and ground: 2 kV (IEC/EN 61000-4-5)
• HF-wire guided: 20 V (IEC/EN 61000-4-6)
• Interference suppression: Limit value classe B (EN 55011)

Degree of protection

• Housing: IP 30 (not sealed) (IEC/EN 60529)
  IP 40 (sealed with seal wire 50/30) (IEC/EN 60529) - The unit must be disconnected from the power supply before the seal is applied.
• Terminals: IP 20 (IEC/EN 60529)

Vibration resistance

Thermoplastic with VO behaviour according to UL subject 94. Amplitude 0.35 mm, Frequency 10 ... 55 Hz (IEC/EN 60068-2-6). Frequency 2 ... 13.2 Hz, 13.2 ... 100 Hz, acceleration ± 0.7 gn (IEC/EN 60068-2-6)

Shock resistance

10 gn / 11 ms, 3 pulses (IEC/EN 60068-2-27)

Climate resistance

40/070/04 (IEC/EN 60068-1)

Terminal designation

• Wire connection Cross section: 0.5 ... 4 mm² (AWG 20 - 10) solid or stranded wire without ferrules
  0.5 ... 2.5 mm² (AWG 20 - 10) stranded wire with ferrules
• Stripping length: 6.5 mm
• Max. fixing torque: 0.5 Nm
• Wire fixing: Box terminal with cross recess screw
• Mounting: DIN rail (IEC/EN 60715)
• Weight: Approx. 200 g

Dimensions

Width x height x depth: 52.2 x 90 x 71 mm

Classification to DIN EN 50155

• Vibration and shock resistance: Category 1, Class B (IEC/EN 61373)
• Service temperature classes: OT1, OT2 compliant
• Protective coating of the PCB: No

UL-Data

• Temperature range Operation: -30 ... +60 °C
• Switching capacity: Pilot duty C300, R300, 5A 250Vac, 2A 30Vdc
• Wire connection: 60 °C / 75 °C copper conductors only, Torque 0.5 Nm
• Test specification: ANSI/UL 60947-1, 5th Edition; ANSI/UL 60947-5-1, 3rd Edition; CAN/CSA-C22.2 No. 60947-1-13, 2nd Edition; CAN/CSA-C22.2 No. 60947-5-1-14, 1st Edition

Info Technical data that is not stated in the UL-Data, can be found in the technical data section.

CCC-Data

• Switching capacity To AC 15: 3 A / AC 230 V (NO contact)
  1 A / AC 230 V (NC contact)

Info Technical data that is not stated in the CCC-Data, can be found in the technical data section.

Standard Types

RN 5897.12/300/61

• Article number: 0067252
• Auxiliary voltage: DC 12 ... 24 V

RN 5897.12/300/61

• Article number: 0066942
• Auxiliary voltage: AC/DC 24 ... 60 V

RN 5897.12/300/61

• Article number: 0066943
• Auxiliary voltage: AC/DC 85 ... 230 V

Outputs:

• 1 changeover contact for pre-warning
• 1 changeover contact for alarm
• Setting range pre-warning: 20 kΩ ... 1 MΩ
• Setting range alarm: 10 kΩ ... 250 kΩ
• Max. line capacitance: 30 µF
• Energized or de-energized on trip
• Selection of type of network
• Width: 52.5 mm

Accessories

Flush mounting kit

Order reference: KU 4087-150/0056598

For universal use with:

• R-series devices of 17.5 to 105 mm width
• Easy mounting

Connection Examples

Single phase mains, isolated from earth

Diagram shows connection for a single-phase mains (AC 0...300V, 40...1000Hz) to the RN5897/300. L1 and L2 are connected to L(+) and L(-). Auxiliary voltage UH is supplied to A1(+)/A2. PE is connected to PE1/PE2. An external combined Test/Reset button is connected to X1/X2. The setting of the type of network is AC.

Ungrounded mains (3N AC)

Diagram shows connection for a 3N AC ungrounded mains (400V/230V, 40...1000Hz) to the RN5897/300. L1, L2, L3, and N are shown. L(+) and L(-) are connected to L1 and L2 respectively. Auxiliary voltage UH is supplied to A1(+)/A2. PE is connected to PE1/PE2. An external combined Test/Reset button is connected to X1/X2. The setting of the type of network is 3N AC.

Ungrounded DC network

Diagram shows connection for an ungrounded DC network (DC 0...300V) to the RN5897/300. L+ and L- are connected to L(+) and L(-). Auxiliary voltage UH is supplied to A1(+)/A2. PE is connected to PE1/PE2. An external combined Test/Reset button is connected to X1/X2. The setting of the type of network is DC.

Notes on Connection Examples:

• Auxiliary voltage U (A1(+)/A2) can also be sourced from the monitored voltage system. The voltage range of the auxiliary supply has to be taken into account.
• Control input X1/X2 for external combined Test-/Reset-button: Control approx. 1 s: Test function; Control > 3 s: Reset function.

Characteristics

The graph titled "Max. measuring time in response to line capacitance RN5897/300" plots the maximum measuring time (TMes in seconds) on the Y-axis against the line capacitance (CE in µF) on the X-axis. It shows different curves for response values RE = 1000 kΩ, RE = 100 kΩ, and RE = 1 kΩ. The maximum line capacitance indicated is 30 µF.