<?php
try {
    $opts = [
        'ssl' => ['ciphers' => 'RC4-SHA', 'verify_peer' => false, 'verify_peer_name' => false],
    ];
    $context = stream_context_create($opts);
    $options = [
        'soap_version' => SOAP_1_2,
        'trace' => true,
        'exceptions' => true,
        'cache_wsdl' => WSDL_CACHE_NONE,
        'connection_timeout' => 10,
        'stream_context' => $context,
        'user_agent' => 'phpSoapClient',
        'ssl_method' => SOAP_SSL_METHOD_TLS/*SOAP_SSL_METHOD_SSLv2*//*SOAP_SSL_METHOD_SSLv3*/,
        'encoding' => 'UTF-8',
        'verifypeer' => false,
        'verifyhost' => false,
    ];
    $client = new SoapClient('https://112.120.74.81/Exchange1C/ws/bgsExchange/?wsdl', $options);
    $req_params = [
        new SoapVar('1', XSD_STRING, null, null, 'sessionKey'),
        new SoapVar('2', XSD_STRING, null, null, 'language'),
        new SoapVar('3', XSD_STRING, null, null, 'calledMethod'),
        new SoapVar('4', XSD_ANYTYPE, null, null, 'methodProperties'),
    ];
    $request_var = new SoapVar($req_params, SOAP_ENC_OBJECT);
    $res = $client->Request($request_var);
    //var_dump($res);die;
    if (isset($res->return)) {
        if ($res->return->success === false) {
            echo $res->return->errors, "\n";
        }
    }
} catch (SoapFault $e) {
    die($e->getMessage() . "\n");
}

Пользователь информационной базы не идентифицирован по sessionKey|Необходимо задать правильное имя метода|Необходимо задать параметры метода 3

<?xml version="1.0" encoding="UTF-8"?>
<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope" xmlns:ns1="http://art-businessgroup.com/exchange1c">
  <env:Body>
    <ns1:Request>
      <ns1:sessionKey>1</ns1:sessionKey>
      <ns1:language>2</ns1:language>
      <ns1:calledMethod>3</ns1:calledMethod>
      <ns1:methodProperties>4</ns1:methodProperties>
    </ns1:Request>
  </env:Body>
</env:Envelope>