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Weighbridge AutomationThe settled weight captured once, time-stamped and sent to your ERP — nothing typed at the cabin

Most weighing indicators publish the weight and a stable flag over Modbus. The gateway watches that one bit: the moment the indicator says the weight has settled, it sends the weighment — weight and time — to your ERP, once per truck, ahead of its routine log interval.

  • Send on settle
  • Weight + time stamp
  • Straight to the ERP
  • Kept through outages
  • Go / wait light
Talk to our engineersWT400M 4G gateway
01

Watch it work

click a step to hold it
RS-485 · Modbus RTU · relay4G / LAN · HTTP + MQTTWeighing indicatorModbus · weight, flag0 kg · stable18,420 kg · moving24,560 kg · stableGo / wait lightRelay → interposerRed · waitGreen · goERP / weighbridge appServer 1 · HTTP POSTWeighbridge dashboardServer 2 · MQTTWiman gatewayTrigger on the stable bitWeighment sentRelay ONRS-485 · Modbus RTU · relay4G / LAN · HTTP + MQTTWeighing indicatorModbus · weight, flag0 kg · stable18,420 kg · moving24,560 kg · stableGo / wait lightRelay → interposerRed · waitGreen · goERP / weighbridge appServer 1 · HTTP POSTWeighbridge dashboardServer 2 · MQTTWiman gatewayTrigger on the stable bitWeighment sentRelay ON
  1. Step 1 of 5The platform is empty. The gateway polls the indicator on its routine interval; there is no weighment to send.
  2. Step 2 of 5A truck drives on. The weight climbs and swings, the indicator's stable flag is off, and the gateway sends nothing yet.
  3. Step 3 of 5The indicator sets its stable bit. A trigger on that one bit fires once, and within a second the settled weight goes to the ERP and the dashboard.
  4. Step 4 of 5A second rule on the same bit switches the relay, and the light turns green for the driver.
  5. Step 5 of 5The truck leaves. When the weight falls below 200 kg a third rule switches the light back, ready for the next truck.
02

What connects to the gateway

EquipmentHow it connectsWhat the gateway reads
Weighing indicator with a Modbus outputRS-485 · Modbus RTU (RS-232 on request)Gross / net weight and the status word with its stable bit
Second weighbridge at the same siteSame RS-485 line, own slave IDIts own weighments, sent as its own packets
Traffic light or barrier interfaceRelay → interposing relayGo or wait, switched by trigger rules
Load cellsTo the indicator, not the gatewayThe indicator does the weighing; the gateway carries its result
03

What the gateway does here

Edge triggerSends on settle, once per truckA rule on the stable bit of the indicator's status word fires once when the bit turns on. Every firing sends the indicator's readings within a second, ahead of the log interval.
ERP deliveryNo typing at the cabinThe weighment reaches your ERP as JSON over HTTP POST — or MQTT, or CSV — with the gateway's time stamp. Nothing is keyed in, so nothing can be keyed in wrong.
Two serversERP and a live view togetherThe ERP and a weighbridge dashboard can each get the weighment at once, in their own formats (PRO and MAX series).
Store & forwardA weighment made offline still arrivesIf the link is down, the weighment is kept in the gateway's log and delivered in order, with the time it was made.
RelayA go / wait light, if you want oneOne rule turns the relay on when the weight settles; another turns it off when the platform is clear.
Several platformsOne gateway, more than one weighbridgeIndicators on the same RS-485 line each take their own slave ID, and each sends its own weighments.
04

Which gateway fits

open a model for its full specification
PRO · 4GWT400M4G from the weighbridge cabin, triggers, relay and two servers — no LAN cable to the office needed.View the WT400M →PRO · EthernetWT600MWhere the cabin is on the plant network: triggers, relay and two servers over the LAN.View the WT600M →MAX · 4G + LANWT460MLAN first and 4G when it drops, for sites where a missed weighment costs money.View the WT460M →ConverterWT20CIf weighbridge software on a PC already polls the indicator over Modbus, the gateway can share that port.View the WT20C →
05

Being straight about it

Your indicator must say when it is stableThe capture keys on a stable flag the indicator publishes over Modbus. An indicator that only streams ASCII text needs another approach — send us its manual first.
The indicator is the legal-for-trade instrumentStamping and verification belong to the indicator and the platform. The gateway carries what the indicator reports, unchanged.
The gateway does not identify the truckVehicle numbers, RFID tags and cameras belong to your weighbridge software. The gateway delivers the weight and the time it settled.
Triggers are a PRO and MAX featureSend-on-settle needs the trigger engine, which the PRO and MAX series carry. The LITE series sends on its log interval only.
06

Questions

How does the gateway know the weight has settled?

Weighing indicators keep a status word with a stable bit. A trigger with the condition (Reg BITAND V1) = V2 picks that one bit and fires once when it turns on, sending the indicator's readings — weight included — within a second.

Does it send every reading while the truck rolls on?

No. Routine readings go on the log interval you set, which can be long. The weighment goes the moment the stable bit turns on, once per truck.

Will it work with my indicator?

If the indicator publishes its weight and a status word over Modbus RTU, yes — on RS-485, or RS-232 on request. Send us the indicator's make and model, or its manual, and we will confirm the registers before you order.

Can it send the weight straight to our ERP?

Yes. The gateway posts JSON over HTTP (or publishes over MQTT, or sends CSV) to the address you give it, with your own field names and an API key if your ERP needs one.

What if the internet is down at the weighbridge?

The weighment is logged in the gateway and delivered in order, with the time it settled, as soon as the link returns.

Can one gateway serve two weighbridges?

Yes, when both indicators are on the RS-485 line with their own slave IDs. Each gets its own stable-bit rule, and each weighment arrives as its own packet.

RS-232 vs RS-485Decode a status wordHow the data reaches your serverShare one indicator between two masters
Tell us the site, the equipment and the server.We will tell you which gateway fits, and configure it before it ships.
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