VTM 2 Manual: Installing and Setting Up the Tank Monitor
The VTM 2 tank monitor shows the fill levels of up to four tanks and the voltages of up to two battery banks, and triggers an alarm at a set tank level or voltage threshold. It runs on DC 8–32 V, fits into an 85 × 85 mm mounting cut-out and can be set up for resistance senders, voltage and current sensors, flow sensor, float switches and Gobius 4. This page summarizes installation, settings and technical data from the user manual.
Manual edition: Rev. 1C, January 2024, software version 1.2 and higher (applies to VTM and VTM 2). · Complete user manual as PDF · Go to the VTM 2 product
Contents
- Scope of delivery and recommended tank sensors
- Installation and connection
- Wiring diagram
- Settings and PIN
- Alarms
- Setting up and calibrating tanks
- Operation
- Software update
- Troubleshooting
- Technical data
- Frequently asked questions
Scope of delivery and recommended tank sensors
Included: VTM tank monitor, 3 pluggable terminals (MVSTB 2.5, 2-, 3- and 9-pin), 1 fuse holder ASH1 with FSS 1 A fuse and the user manual.
| Tank type | Recommended sensor (not included) | Order no. |
|---|---|---|
| Fresh water | DFS flow sensor (1×) | 7 0003 0304 |
| Fresh water | TGW 200–800 dip-tube sensor | 6 6011 7xxx |
| Fresh water | TDN200 pressure sensor | 6 6025 1208 |
| Petrol | TGT 200–900 dip-tube sensor | 6 6011 7xxx |
| Diesel | TGT 200–900 dip-tube sensor | 6 6011 7xxx |
| Diesel | TDS200 pressure sensor | 6 6026 1206 |
| Grey water / black water | TDN200 pressure sensor | 6 6025 1208 |
| Grey water / black water | UTV 20–80 ultrasonic tank sensor | 7 0219 35xx |
| Accessories for ultrasonic sensor | Order no. |
|---|---|
| UFT 40 sound guide tube (40 cm long) | 7 0219 9400 |
| UFT 80 sound guide tube (80 cm long) | 7 0219 9800 |
| UTS 25 spacer ring (25 mm high) | 7 0219 9025 |
| Fuse holder incl. 1 A fuse for measuring cables ASH1A | 6 0030 3411 |
Sensors from other manufacturers can also be connected. Note from the manual: only with the DFS flow sensor is the litre display accurate, because it measures litres. With all other sensors the measured fill level is merely converted and, depending on sensor accuracy, can never be accurate to the litre. Matching senders: TGW, TGT, UTV, TDS / TDN 200, DFS 24. The tank sender finder shows which one suits your tank.
Installation and connection
Place of use: The monitor is designed for yachts, runs only on extra-low voltage DC 8–32 V and belongs in enclosed spaces, protected from rain, moisture, dust and condensation. Do not install it outdoors or where there is a risk of explosion from gas or dust. Connection may only be carried out by qualified electricians; disconnect the battery cables beforehand and observe the correct polarity. The supply cable to the power supply must be fused.
- Mount in a protected, dry and clearly visible place so that the monitor can be read at any time.
- Mounting cut-out 85 × 85 mm, minimum depth required 35 mm.
- On the back: 3-pin terminal for the power supply, 9-pin terminal for the tank sensors, 2-pin terminal for the potential-free relay contact, micro SD slot for software updates.
- The voltage of the first battery is measured at the plus terminal (12/24 V) of the supply, that of the second at terminal Batt.2+.
Connecting tank sensors
- Up to four tanks. With fewer tanks: the first sensor goes to TG 1; with two sensors only TG 1 and TG 2 are used.
- Resistance sensors (e.g. TGT, TGW) and active sensors (e.g. TDS pressure sensor) may be connected mixed.
- A DFS flow sensor goes only to the DFS terminals (DFS+ / Minus / DFS S). TG 1 must then remain free, because the DFS can only be activated via tank 1. A maximum of one DFS may be connected.
- If the supply (red wire) of an ultrasonic sensor is not powered via the VTM but directly from the DC on-board system, it must be fused with 1 A.
- The negative wires of the tank sensors belong on the Minus (−) terminal to avoid incorrect measurements.
Wiring diagram
Diagram from the user manual, from top to bottom: voltage measurement of the starter and the house battery (Batt.2+ and 12/24 V, each fused with 1 A), TGx resistance senders on TG 1–4 and Minus, TDx pressure sensor (4–20 mA) and UTV ultrasonic sensor with the wire colours red, black and yellow, DFS flow sensor on DFS S, DFS+ and Minus.
Settings and PIN
You open the settings via the gear symbol at the bottom right of the main screen. The PIN is 1234 as delivered. Submenus: Display, Battery, Alarms and the tank settings (1–4) on the second page.
| Setting (Display menu) | Values |
|---|---|
| Language | DE / FR / GB … |
| Max. brightness | 15–100 % |
| Auto brightness | ON / OFF |
| Auto standby | OFF / x s / min |
| Night mode threshold | 3…30 |
| More | Change PIN, number of tanks, tank content unit (L/g), load factory settings, battery voltage display, software version |
Calibrating the night mode threshold: Cover the light sensor (centre left of the display) with your finger and read the value in brackets. Add two to this value and enter it. If the measured value falls below the threshold, the display is dimmed; if it exceeds the threshold +10, it lights up normally again.
Alarms
A tank alarm is indicated by the tank symbol flashing, a voltage alarm in the battery symbol. They can also be output visually (display backlight flashes), audibly (internal buzzer) and via the potential-free relay (max. 1 A). Visual and audible alarms are acknowledged by touching the screen or switch off by themselves after an adjustable time (0–255 s, 0 = always on).
| Alarm | Setting range |
|---|---|
| Tank 1–4 | 0 % alarm off, 1–50 % empty alarm, 51–99 % full alarm, each delayed by 15 s; the alarm clears at a 5 % change in value |
| Battery 1 and 2: undervoltage | 9–24 V |
| Battery 1 and 2: overvoltage | 14–32 V |
If more than 8 V is present at Batt.2+, this is reported as a battery; a voltage alarm is raised when the voltage exceeds or falls below the threshold for 20 s. For 24 V batteries the voltage alarms must be adjusted without fail.
Setting up and calibrating tanks
The tank menu opens via the arrow button next to the tank. There you set the tank type (water, diesel, petrol, black water, grey water), volume (max. 9999 l) and sensor type. If the tank type does not match the sensor, the monitor shows “---” or a wrong value.
| Sensor type | Tank sensor / range | Adjustment |
|---|---|---|
| TGX 10–180 (ohm) | philippi TGT / TGW, 10–180 Ω (10 Ω empty, 180 Ω full) | optional |
| 240–33 (ohm) | 240 Ω empty, 33 Ω full | optional |
| User R | passive resistance sensor 1–1000 Ω | required |
| User V (UTV) | voltage signal up to 0–10 V, factory setting UTV 0.5–2.5 V | required |
| UTV 40/80 | UTV 40 up to 40 cm tank depth, UTV 80 from 40 to 80 cm; enter tank depth in cm | optional |
| TDS / 4–20 mA | current output 4–20 mA, e.g. TDS200, TDN200, TDT 250 | required |
| DFS (down / up) | DFS flow sensor, tank 1 only, enter fill level manually | not possible |
| TRS | TRS float switch (top) or RSW/DSW (side), without series resistor | not possible |
| Gobius4 | Gobius 4 (1–4 V), display in 4 steps | not possible |
With DFS (down) the tank is emptied on the display, with DFS (up) it is filled, for example to record the output of a watermaker. With sensor type User R the setting only works with passive resistance sensors, not with capacitive or active resistance sensors (e.g. philippi UTR).
Calibration (mandatory for User R, User V and TDS), three ways:
- Filling step by step: With the tank empty, read the measured value at the bottom centre and enter it at 0 %, then repeat at 25, 50, 75 and 100 % fill. Gives the correct content even with an unusual tank shape.
- With a full tank (e.g. TDS200): Enter the measured value with the sensor outside the tank at 0 %, after installation at 100 %. Divide the difference by 4 and add it step by step to obtain 25, 50 and 75 %.
- Values known: Enter the values for 0, 25, 50, 75 and 100 % directly.
More on selecting and installing the senders: Measuring tank fill levels.
Operation
The tank screen shows the fill levels as a bar chart; measurement runs automatically and is polled every 5 seconds. Pressing the tank symbol switches the display between percent, litres and no additional display. At the bottom, up to two voltages of the auxiliary batteries appear, whose names and alarm thresholds are adjustable.
Software update
- Copy the update file to an empty micro SD card (FAT32), without folders, to the top level.
- Slide the card into the slot on the back and disconnect the power supply.
- Switch the power supply back on. The monitor detects the new software, installs it automatically and shows the progress.
If the monitor starts normally, no card was detected or the software is already up to date.
Troubleshooting
- Display is incorrect: first check the tank sensors and their cables, as they are usually the cause. In the Adjustment menu you can read the sensor’s current measured value.
- “----” above the tank: The measured value is outside the expected range, or no sensor is connected.
- Tank type and sensor type do not match: “---” or a wrong value appears.
Technical data
| Supply voltage | DC 8–32 V |
| Monitor current consumption (without tank sensor) | 83 mA at maximum display brightness, 7 mA in sleep mode |
| Measuring range U1 / U2 | 8–32 V each, resolution 30 mV, accuracy 0.25 % |
| Relay | potential-free, max. 1 A |
| Monitor dimensions | 105 × 105 × 40 mm |
| Mounting cut-out / minimum depth | 85 × 85 mm / 35 mm |
| Conformity | EMC Directive 2014/30/EG, EN 61000-6-1, EN 61000-6-3 |
Warranty: two years from the date of purchase, for material or manufacturing defects. For questions about installation or for a repair: Contact · Warranty and repair · All user manuals. For additional battery monitoring and NMEA 2000: BTM2 manual.
Frequently asked questions
What is the PIN for the VTM 2 settings?
The PIN is 1234 when delivered. On the main screen, press the gear symbol at the bottom right, enter the PIN and confirm with OK. You then reach the Display, Battery and Alarms settings and the tank settings for tanks 1 to 4. You can change the PIN in the Display menu. Tank settings stay saved if the supply fails.
How do I connect several tank sensors to the VTM 2?
The VTM 2 monitors up to four tanks. The first sensor goes to TG 1, the others follow in order. Resistance sensors such as TGT and TGW may be mixed with active sensors such as the TDS pressure sensor. A DFS flow sensor goes to the DFS terminals, leaving TG 1 free. Only one DFS can be connected.
How do I set alarms for tank levels?
You can set an alarm threshold for each of the four tanks. Values from 1 to 50 percent trigger an empty alarm, 51 to 99 percent a full alarm, each delayed by 15 seconds; 0 percent switches the alarm off. You can also assign the buzzer and the potential-free relay (1 A maximum). Touching the screen acknowledges the alarm.
What does the display with four dashes above a tank mean?
If the tank screen shows four dashes, the sensor reading is outside the expected range or no sensor is connected. First check the tank sensors and their cables, as they are usually the cause. The Adjustment menu shows the current measured value. If the tank type does not match the sensor, no value or a wrong value appears as well.
